Eavesdropping On the Electromagnetic Emanations of
     Digital Equipment: The Laws of Canada, England and
                     the United States



          Copyright (C) 1989 By Christopher Seline

     This document is a rough draft. The Legal Sections
        are  overviews.  They will be significantly
               expanded  in the next version.







     We in this country, in this generation, are --  by
     destiny  rather than choice -- the watchmen on the
     walls of world freedom.1
                       -President John F. Kennedy




In the novel 1984, George Orwell  foretold  a  future  where
individuals had no expectation  of privacy because the state
monopolized  the  technology  of   spying.   The  government
watched the actions of its subjects from birth to death.  No
one could protect himself because surveillance and  counter-
surveillance technology was controlled by the government.

This note explores  the  legal  status  of   a  surveillance
technology  ruefully  known  as  TEMPEST2.    Using  TEMPEST
technology  the  information in  any  digital device  may be
intercepted  and  reconstructed  into   useful  intelligence
without the operative ever  having to come near his  target.
The technology is  especially useful in the  interception of
information  stored  in digital  computers  or displayed  on
computer terminals.


_________________________
1.  Undelivered  speech  of  President  John  F.   Ken-
nedy, Dallas Citizens Council (Nov. 22, 1963) 35-36.
2.  TEMPEST  is an  acronym for  Transient  Electromag-
netic  Pulse  Emanation  Standard.   This standard sets
forth the official views of the United  States  on  the
amount   of electromagnetic radiation that a device may
emit without compromising the information  it  is  pro-



                        June 7, 1990





                           - 2 -


The use of TEMPEST is not illegal  under  the  laws  of  the
United  States3,  or  England.    Canada has  specific  laws
criminalizing TEMPEST eavesdropping but the  laws do more to
hinder surveillance countermeasures than  to prevent TEMPEST
surveillance.  In  the United  States it is  illegal for  an
individual  to  take   effective  counter-measures   against
TEMPEST surveillance.   This leads to the  conundrum that it
is legal  for individuals and  the government to  invade the
privacy of others but illegal for individuals to  take steps
to protect their privacy.

The author would like to  suggest that the solution  to this
conundrum   is    straightforward.     Information   on pro-
tecting  privacy  under  TEMPEST  should   be   made  freely
available;  TEMPEST Certified  equipment  should be  legally
available; and organizations possessing  private information
should  be  required  by  law  to protect  that  information
through  good  computer security  practices  and the  use of
TEMPEST Certified equipment.

Spying is divided by  professionals  into  two  main  types:
human   intelligence   gathering  (HUMINT)   and  electronic
intelligence gathering (ELINT).  As  the names imply, HUMINT
relies   on   human   operatives,  and   ELINT   relies   on
technological operatives.  In the  past HUMINT was the  sole
method for  collecting intelligence.4  The  HUMINT operative
would  steal  important  papers,  observe troop  and  weapon
movements5, lure  people  into his  confidences  to  extract
secrets,  and   stand  under  the   eavesdrip6  of   houses,
eavesdropping on the occupants.


_________________________
cessing.   TEMPEST is  a  defensive standard;  a device
which conforms to this standard is referred to as  TEM-
PEST Certified.
The United States  government has refused to  declassi-
fy the acronym  for   devices  used  to  intercept  the
electromagnetic information of   non-TEMPEST  Certified
devices.    For  this   note,  these  devices  and  the
technology  behind  them  will  also  be  referred   to
as  TEMPEST;   in   which   case,  TEMPEST  stands  for
Transient Electromagnetic Pulse Surveillance  Technolo-
gy.
The  United  States  government   refuses   to  release
details  regarding  TEMPEST  and continues an organized
effort to  censor  the  dissemination   of  information
about   it.    For  example the  NSA succeeded in shut-
ting  down a  Wang Laboratories presentation   on  TEM-
PEST  Certified equipment  by classifying  the contents
of  the  speech  and  threatening   to  prosecute   the
speaker  with  revealing classified information.  [cite
coming].
3.  This  Note  will not  discuses   how   TEMPEST  re-



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                           - 3 -


As  technology has  progressed, tasks  that  once could only
be   performed   by   humans   have   been   taken  over  by
machines.  So  it has  been with spying.   Modern  satellite
technology allows troop and weapons movements to be observed
with greater  precision and  from greater  distances than  a
human  spy  could ever  hope to  accomplish.   The  theft of
documents  and  eavesdropping on  conversations  may now  be
performed electronically.  This means greater safety for the
human operative, whose  only involvement may be  the placing
of  the  initial  ELINT  devices.    This  has  led  to  the
ascendancy of ELINT  over HUMINT  because the placement  and
monitoring of ELINT devices may be performed by a technician
who has  no training  in the  art of  spying.   The gathered
intelligence may  be processed  by  an intelligence  expert,
perhaps  thousands of  miles  away, with  no  need of  field
experience.


ELINT has a number of other advantages over  HUMINT.   If  a
spy  is  caught his existence could  embarrass his employing
state and he could  be forced into giving up  the identities
of his compatriots or  other important information.   By its
very  nature, a discovered ELINT device (bug) cannot give up
any information; and the ubiquitous  nature of bugs provides
the  principle  state  with the  ability  to  plausibly deny
ownership or involvement.
_________________________
lates   to   the  Warrant Requirement under  the United
States Constitution.   Nor will it discuss the  Consti-
tutional  exclusion  of foreign nationals from the War-
rant Requirement.
4.  HUMINT  has  been  used  by  the    United   States
since   the  Revolution.   "The necessity  of procuring
good intelligence  is apparent &  need not  be  further
urged  --   All that remains for me to add is, that you
keep the  whole matter  as  secret  as  possible.   For
upon Secrecy,  Success depends  in Most  Enterprises of
the kind, and for  want of it,  they are generally  de-
feated,   however well planned &  promising a favorable
issue."  Letter of  George Washington (Jul. 26, 1777).
5.  "... I wish  you to take every  possible  pains  in
your  powers,  by   sending  trusty persons  to  Staten
Island in  whom  you can confide,  to  obtain  Intelli-
gence   of   the Enemy's  situation  & numbers --  what
kind of  Troops they are,  and what  Guards  they  have
-- their strength & where posted."  Id.
6.  Eavesdrip is  an Anglo-Saxon  word,  and refers  to
the  wide overhanging eaves used  to prevent rain  from
falling close to  a house's foundation.   The eavesdrip
provided "a sheltered  place where  one  could hide  to
listen  clandestinely   to  conversation   within   the
house."    W. MORRIS & M. MORRIS,  MORRIS DICTIONARY OF
WORD AND PHRASE ORIGINS, 198 (1977).




                        June 7, 1990





                           - 4 -


ELINT   devices   fall    into    two   broad    categories:
trespassatory  and  non-trespassatory.   Trespassatory  bugs
require some type of trespass in order for them to function.
A transmitter  might require  the physical  invasion of  the
target  premises  for placement,  or  a microphone  might be
surreptitiously  attached to  the outside  of  a window.   A
telephone transmitter can  be placed  anywhere on the  phone
line, including  at the central switch.   The trespass comes
either when it is physically attached  to the phone line, or
if it is  inductive, when placed  in close proximity to  the
phone  line.  Even  microwave bugs require  the placement of
the resonator cone within the target premises.7

Non-trespassatory   ELINT   devices   work    by   receiving
electromagnetic  radiation (EMR) as  it radiates through the
aether, and do not  require the placement of bugs.   Methods
include intercepting8 information transmitted  by satellite,
microwave, and  radio, including  mobile and cellular  phone
transmissions.   This information was  purposely transmitted
with  the intent that some  intended person or persons would
receive it.

Non-trespassatory ELINT also includes  the  interception  of
information  that   was  never  intended to be  transmitted.
All electronic devices emit electromagnetic radiation.  Some
of  the  radiation, as  with  radio  waves, is  intended  to
transmit  information.    Much  of  this  radiation  is  not
intended to transmit information and is merely incidental to
whatever  work  the  target  device  is performing.9    This
information  can be  intercepted  and  reconstructed into  a
coherent  form.    With  current  TEMPEST technology  it  is
possible  to  reconstruct  the  contents of  computer  video
display  terminal  (VDU)  screens  from  up to  a  kilometer
distant10;  reconstructing  the  contents  of  a  computer's
memory or the contents  of its mass storage devices  is more
complicated and must be performed  from a closer distance.11
The reconstruction  of information  via EMR,  a process  for
which the  United  States government  refuses to  declassify
either  the  exact technique  or  even  its name12,  is  not
limited to computers  and digital devices but  is applicable
to  all devices  that generate  electromagnetic radiation.13
TEMPEST is  especially effective  against VDUs  because they
produce a very high level of EMR.14
_________________________
7.  Pursglove, How  Russian Spy   Radios  Work,   RADIO
ELECTRONICS, 89-91 (Jan 1962).
8.  Interception  is  an  espionage term  of  art   and
should  be  differentiated from its  more common usage.
When information is intercepted,  the  interceptor   as
well   as  the intended  recipient receive the informa-
tion.  Interception when not used  as  a  term  of  art
refers  to  one person receiving something intended for
someone else; the intended   recipient  never  receives
what he was intended to receive.



                        June 7, 1990





                           - 5 -


     "[C]ables  may act  as  an  antenna   to  transmit
     the  signals directly  or  even both  receive  the
     signals  and re-emit  them further away  from  the
     source  equipment.    It  is possible  that cables
     acting as an  antenna  in  such  a  manner   could
     transmit  the  signals   much   more   efficiently
     than the  equipment   itself...A  similar   effect
     may  occur   with metal  pipes  such as  those for
     domestic  water  supplies.  ...   If  an  earthing
     [(grounding)]  system is  not installed  correctly
     such that  there is  a path  in the circuit   with
     a very  high resistance  (for example  where paint
     prevents  conduction and  is  acting as  an  insu-
     lator),   then  the  whole   earthing system could
     well act in  a similar fashion to an antenna.  ...
     [For a  VDU] the strongest  signals, or  harmonics
     thereof, are  usually between  60-250 MHz  approx-
     imately.    There  have  however  been  noticeable
     exception  of   extremely   strong  emissions   in
     the  television bands  and  at  higher frequencies
     between 450-800  MHz.  Potts,  Emission  Security,
     3  COMPUTER LAW AND SECURITY REPORT 27 (1988).


_________________________
9.  There are  two types  of emissions,  conducted  and
radiated.   Radiated  emissions   are formed when  com-
ponents or cables  act as  antennas  for  transmit  the
EMR;  when radiation is conducted along cables or other
connections but not radiated it is referred to as "con-
ducted".   Sources   include  cables,  the ground loop,
printed circuit  boards,  internal  wires,   the  power
supply  to power line
10. The TEMPEST ELINT operator can distinguish  between
different  VDUs   in    the   same  room   because   of
the   different   EMR characteristics of both  homo and
heterogeneous  units.    "[T]here is little  comparison
between EMR characteristics  from otherwise  comparable
equipment.    Only if the  [VDU] was made with  exactly
the  same components is  there  any   similarity.    If
some   of  the  components  have  come from a different
batch, have been updated in some  way,   and  especial-
ly   if    they  are  from   a  different manufacturer,
then completely different  results  are  obtained.   In
this way a  different mark or version of the same [VDU]
will emit different  signals.    Additionally   because
of  the   variation  of manufacturing standards between
counties, two  [VDUs] made by the  same   company   but
sourced   from  different counties  will  have entirely
different EMR signal characteristics...From this it way
be  thought  that  there  is such a jumble of emissions
around, that it would not be possible to isolate  those
from any one particular source.  Again, this is not the
case.  Most received signals  have  a   different  line



                        June 7, 1990





                           - 6 -


ELINT is not limited to  governments.  It is  routinely used
by   individuals  for   their  own   purposes.   Almost  all
forms of ELINT are  available to the individual  with either
the technological  expertise or  the money  to hire  someone
_________________________
synchronization,   due   to  design,   reflection,  in-
terference or  variation of component  tolerances.   So
that  if  for   instance   there  are  three  different
signals  on the  same frequency  ...  by  fine   tuning
of    the   RF   receiver,   antenna  manipulation  and
modification  of line  synchronization,  it  is  possi-
ble  to  lock onto each of the three signals separately
and so read  the  screen   information.    By   similar
techniques,  it  is entirely  possible to  discriminate
between  individual items  of  equipment  in  the  same
room."   Potts,  supra  note  9.  For  a  discussion of
the  TEMPEST ELINT   threat   See  e.g.,  Memory  Bank,
AMERICAN  BANKER  20  (Apr 1 1985); Emissions from Bank
Computer   Systems  Make  Eavesdropping   Easy,  Expert
Says, AMERICAN BANKER  1  (Mar  26 1985);  CRT  spying:
a  threat to   corporate  security,  PC  WEEK  (Mar  10
1987).
11.  TEMPEST  is  concerned  with  the transient  elec-
tromagnetic pulses formed  by digital  equipment.   All
electronic  equipment  radiates   EMR   which   may  be
reconstructed.     Digital equipment processes informa-
tion as 1's and 0's--on's  or off's.  Because of  this,
digital  equipment   gives  off  pulses  of EMR.  These
pulses are easier to  reconstruct at a   distance  than
the  non-pulse   EMR  given  off  by  analog equipment.
For a  thorough discussion  the radiation  problems  of
broadband   digital   information  see   e.g.  military
standard  MIL-STD-461    REO2;  White  supra  note   9,
10.2.
12.  See supra note 2.
13.       Of special interest  to ELINT  collectors are
EMR   from  computers,   communications    centers  and
avionics.     Schultz, Defeating Ivan with TEMPEST, DE-
FENSE ELECTRONICS 64 (June 1983).
14.     The  picture  on a  CRT  screen is   built   up
of   picture  elements   (pixels)  organized   in lines
across the  screen.   The pixels  are  made of  materi-
al  that  fluoresces when  struck with energy.  The en-
ergy is produced by a beam of electrons fired  from  an
electron  gun   in the back of  the picture tube.   The
electron beam scans the screen of the  CRT in a regular
repetitive  manner.   When  the  voltage of the beam is
high then the pixel it is focused upon   emits  photons
and appears  as  a dot  on the  screen.   By selective-
ly  firing the gun  as it scans  across  the  face   of
the CRT, the pixels form characters on the CRT screen.
     The  pixels glow  for only   a  very   short  time
and   must be routinely struck by  the electron beam to
stay lit.   To maintain the light  output  of  all  the



                        June 7, 1990





                           - 7 -


with  the   expertise.    Governments   have  attempted   to
criminalize all use  of ELINT by their  subjects--to protect
the privacy of both the government and the population.


In the  United States, Title III of the Omnibus Streets  and
Crimes Act of 196815 criminalizes trespassatory ELINT as the
intentional interception of  wire communications.16  As ori-
ginally   passed,    Title   III  did   not  prohibit   non-
trespassatory ELINT,17  because courts  found that  non-wire
communication lacked  any expectation of p2IIIrivacy.18  The
Electronic Communications  Privacy  Act  of  198619  amended
Title  III  to  include non-wire  communication.    ECPA was
specifically  designed to  include  electronic mail,  inter-
computer  communications,  and  cellular  telephones.     To
accomplish  this,  the  expectation  of  privacy  test   was
eliminated.20
_________________________
pixels  that are supposed to be  lit, the electron beam
traverses  the entire CRT screen sixty  times a second.
Every  time   the  beam fires it causes a  high voltage
EMR emission.  This  EMR can be  used   to  reconstruct
the   contents  of  the   target CRT  screen.   TEMPEST
ELINT  equipment designed  to reconstruct the  informa-
tion synchronizes its  CRT with the target CRT.  First,
it uses the EMR to synchronize its  electron  gun  with
the  electron  gun  in  the target CRT.  Then, when the
TEMPEST ELINT unit detects EMR indicating that the tar-
get CRT fired on a pixel, the TEMPEST ELINT  unit fires
the electron  gun of its CRT.   The  ELINT  CRT  is  in
perfect  synchronism with the target CRT; when the tar-
get lights a pixel, a corresponding pixel on  the  TEM-
PEST  ELINT CRT is lit.   The exact picture on the tar-
get  CRT will appear on the  TEMPEST  ELINT  CRT.   Any
changes  on  the  target  screen  will be instantly re-
flected in the TEMPEST ELINT screen.
     TEMPEST Certified equipment  gives  off  emissions
levels  that  are  too  faint  to  be readily detected.
Certification  levels  are  set    out    in   National
Communications     Security    Information   Memorandum
5100A   (NACSIM  5100A).    "[E]mission    levels   are
expressed  in the time and  frequency domain, broadband
or  narrow band in terms of  the frequency domain,  and
in  terms  of conducted or radiated emissions."  White,
supra, note 9,   10.1.
     For a  thorough  though purposely  misleading dis-
cussion  of TEMPEST ELINT see  Van Eck, Electromagnetic
Radiation  from Video Display units:  An  Eavesdropping
Risk?, 4 Computers & Security 269 (1985).
15.    Pub.   L.  No.  90-351, 82 Stat.  197.  The  Act
criminalizes trespassatory  ELINT  by  individuals   as
well   as   governmental  agents.   cf.  Katz v. United
States, 389 U.S. 347 (1967) (Fourth Amendment prohibits
surveillance by government not individuals.)



                        June 7, 1990





                           - 8 -


As  amended, Title   III   still   outlaws  the   electronic
interception of  communications.  The  word "communications"
indicates  that   someone  is   attempting  to   communicate
something to someone;  it does not refer to  the inadvertent
transmission   of   information.      The   reception    and
reconstruction of emanated transient  electromagnetic pulses
(ETEP), however, is based on  obtaining information that the
target  does not  mean  to transmit.   If  the  ETEP is  not
intended as communication, and  is therefore not transmitted
in a form approaching current communications protocols, then
it can not  be considered communications as  contemplated by
Congress  when  it   amended  Title  III.     Reception,  or
interception, of emanated  transient electromagnetic  pulses
is not criminalized by Title III as amended.

In  England   the   Interception   of   Communications   Act
198521 criminalizes the tapping of communications  sent over
public  telecommunications  lines.22   The  interception  of
communications on  a telecommunication  line can  take place
with a physical tap on the line, or the passive interception
of microwave or satellite  links.23  These forms  of passive
interception differ  from  TEMPEST ELINT  because  they  are
intercepting   intended    communication;   TEMPEST    ELINT
intercepts unintended communication.   Eavesdropping on  the
emanations  of computers  does  not in  any  way comport  to
tapping a telecommunication line and therefore falls outside
the scope of the statute.24
_________________________
16.  18 U.S.C.   2511(1)(a).
17.  United States v. Hall,  488  F.2d  193  (9th  Cir.
1973)   (found   no   legislative  history   indicating
Congress  intended the act  to include  radio-telephone
conversations).   Further,  Title III only criminalized
the interception  of  "aural" communications  which ex-
cluded all forms of computer communications.
18.  Willamette  Subscription Television   v.   Cawood,
580  F.Supp 1164 (D. Or. 1984) (non-wire communications
lacks any expectation of privacy).
19.  Pub. L. No. 99-508, 100 Stat. 1848 (codified at 18
U.S.C.  2510-710) [hereinafter ECPA].
9           20.  18 U.S.C.   2511(1)(a) criminalizes the
interception  of  "any wire,  oral  or electronic  com-
munication"   without  regard   to  an  expectation  of
privacy.
21.  Interception of Communications Act 1985,  Long Ti-
tle, An Act to make new provision for and in connection
with  the  interception  of   communications   sent  by
post   or  by   means  of    public  telecommunications
systems   and  to  amend  section  45  of  the Telecom-
munications Act 1984.
22.  Interception  of  Communications  Act  1985     1,
Prohibition on Interception:
(1) Subject to the  following provisions of  this  sec-
tion,   a  person  who intentionally intercepts  a com-


9                        June 7, 1990





                           - 9 -


Canada has taken direct steps to limit eavesdropping on com-
puters.     The  Canadian   Criminal  Amendment Act  of 1985
criminalized indirect access  to a computer service.25   The
specific reference  to an  "electromagnetic device"  clearly
shows the intent  of the legislature  to include the use  of
TEMPEST ELINT equipment within the ambit of the legislation.

The limitation of obtaining "any computer service" does lead
to  some confusion.   The Canadian  legislature has not made
it  clear  whether  "computer  service"  refers  to  a  com-
puter   service   bureau   or  merely   the  services  of  a
computer.    If  the  Canadians  had  meant  access  to  any
computer,  why  did they  refer  to any  "computer service".
This   is   especially   confusing   considering   the   al-
encompassing language  of (b)  'any function  of a  computer
system'.

Even    if    the    Canadian    legislation    criminalizes
eavesdropping  on  all  computers,  it  does not  solve  the
problem  of  protecting  the privacy  of  information.   The
purpose of  criminal  law is  to  control crime.26    Merely
_________________________
munication in the course of  its transmission  by  post
or   by  means  of  a  public telecommunications system
shall be guilty  of an offence and liable--
(a) on summary conviction,to a fine not  exceeding  the
statutory maximum;
(b) on conviction on indictment,  to imprisonment for a
term not exceeding two years or to a fine or to both.
23.  Tapping  (aka   trespassatory  eavesdropping)   is
patently  in  violation  of the statute.  "The  offense
created by section 1 of the Interception of  Communica-
tions  Act  1985 covers those forms of eavesdropping on
computer communications  which  involve  "tapping"  the
wires  along   which  messages  are being passed.   One
problem which  may  arise,  however,  is  the  question
of   whether  the communication in question  was inter-
cepted in  the course of  its transmission by  means of
a  public telecommunications system.  It is technically
possible  to  intercept  a  communication   at  several
stages  in  its transmission,  and it may be a question
of fact to decide the stage  at  which  it  enters  the
"public"  realm.   THE LAW COMMISSION,WORKING PAPER NO.
110: COMPUTER MISUSE,  3.30 (1988).
24.  "There are  also forms of  eavesdropping which the
Act  does  not cover.  For  example. eavesdropping on a
V.D.U.  [referred to in  this text as a CRT] screen  by
monitoring  the  radiation field which surrounds it  in
order to  display whatever appears on   the  legitimate
user's   screen  on  the  eavesdropper's screen.   This
activity would not  seem to   constitute  any  criminal
offence..."  THE LAW COMMISSION, WORKING PAPER NO. 110:
COMPUTER MISUSE,  3.31 (1988).




                        June 7, 1990





                           - 10 -


making  TEMPEST  ELINT  illegal will  not  control  its use.
First,  because  it is  an  inherently passive  crime  it is
impossible  to detect and hence punish.  Second, making this
form  of eavesdropping  illegal  without taking  a proactive
stance  in  controlling  compromising  emanations gives  the
public a false sense of  security.  Third, criminalizing the
possession of a TEMPEST ELINT  device prevents public sector
research into countermeasures.   Finally,  the law will  not
prevent eavesdropping on private information held in company
computers unless disincentives are given for  companies that
do not take sufficient precautions against eavesdropping and
simple, more common, information crimes.27


TEMPEST ELINT  is  passive.    The   computer  or   terminal
emanates compromising radiation which is  intercepted by the
TEMPEST  device and  reconstructed into  useful information.
Unlike conventional  ELINT there  is no  need to  physically
_________________________
25.   301.2(1) of the  Canadian  criminal  code  states
that anyone who without color of right,
(a) obtains, directly or indirectly, any computer  ser-
vice,
(b)  by  means  of  an   electromagnetic  ...  or  oth-
er   device, intercepts  or  causes  to  be  intercept-
ed, either  directly  or indirectly, any function of  a
computer  system  ...  [is  guilty of an indictable of-
fence].
26.  UNITED   STATES    SENTENCING    COMM'N,   FEDERAL
SENTENCING GUIDELINES MANUAL (1988) (Principles Govern-
ing  the Redrafting of the Preliminary Guidelines  "g."
(at an unknown page))
27.  There has been great debate over  what exactly  is
a  computer  crime.    There  are  several  schools  of
thought.    The  more articulate school, and the one to
which  the author adheres holds that the  category com-
puter  crime should  be  limited  to   crimes  directed
against  computers; for example, a terrorist destroying
a  computer  with  explosives  would   fall  into  this
category.    Crimes such  as  putting  ghost  employees
on  a  payroll computer  and collecting their  pay  are
merely  age-old accounting frauds; today the  fraud in-
volves a computer because  the records are  kept  on  a
computer.   The   computer  is merely ancillary to  the
crime.  This has been  mislabeled  computer  crime  and
should   merely  be referred to as a fraud  perpetrated
with the aid of a  computer.  Finally, there are infor-
mation  crimes.  These  are crimes related to  the pur-
loining or alteration  of information.   These   crimes
are  more  common  and  more  profitable  due  to   the
computer's ability to hold and access great amounts  of
information.   TEMPEST ELINT can best be categorized as
a information crime.




                        June 7, 1990





                           - 11 -


trespass or even come near the target.  Eavesdropping can be
performed from a nearby office or even a van parked within a
reasonable distance.   This means  that there is  no classic
scene of the crime; and little or no chance of  the criminal
being discovered in the act.28

If the crime is discovered it  will  be  ancillary  to  some
other  investigation.    For example,  if  an  individual is
investigated for insider  trading a search of  his residence
may yield a TEMPEST ELINT device.   The device would explain
how the defendant was obtaining  insider information; but it
was the insider trading, not the  device, that gave away the
crime.

This  is  especially  true  for  illegal TEMPEST  ELINT per-
formed by the state.  Unless the  perpetrators are caught in
the act  there is little  evidence  of   their  spying.    A
trespatory  bug  can  be detected and located; further, once
found it provides tangible evidence that a crime took place.

A TEMPEST ELINT device by its inherent passive nature leaves
nothing to detect.   Since the government is less  likely to
commit an ancillary crime which might be detected there is a
very small chance that  the spying will ever  be discovered.
The  only way to  prevent eavesdropping is  to encourage the
use of  countermeasures: TEMPEST  Certified29 computers  and
terminals.

In merely making  TEMPEST  ELINT   illegal  the  public   is
given the  false impression  of security;  they lulled  into
believing  the  problem  has been  solved.    Making certain
actions illegal does not prevent them from  occurring.  This
is  especially true  for  a  TEMPEST  ELINT  because  it  is
undetectable.  Punishment is an empty  threat if there is no
chance  of being detected; without detection there can be no
apprehension and conviction.   The only way  to prevent some
entity  from eavesdropping  on  one's  computer or  computer
terminal is for  the equipment not to  give off compromising
emanation; it must be TEMPEST Certified.
_________________________
28.  Compare, for  example, the  Watergate breakin   in
which   the  burglars   were discovered  when  they re-
turned  to move  a poorly placed spread spectrum bug.
29.  TEMPEST Certified refers  to the  equipment having
passed   a  testing and emanations  regime specified in
NACSIM 5100A.   This classified document sets forth the
emanations  levels that the NSA believes digital equip-
ment can give  off without compromising the information
it   is  processing.   TEMPEST  Certified equipment  is
theoretically secure against TEMPEST eavesdropping.
     NACSIM 5100A is  classified, as  are  all  details
of  TEMPEST.   To   obtain   access  to  it, contractor
must  prove that  there is demand within  the   govern-
ment for the specific  type of equipment that intend to



                        June 7, 1990





                           - 12 -


The  United States can  solve  this  problem   by  taking  a
proactive stance  on compromising emanations.   The National
Institute of Standards and Technology  (NIST30) is in charge
of  setting  forth standards  of  computer security  for the
private  sector.   NIST  is also  charged  with doing  basic
research to advance the art of computer security.  Currently
NIST does not discuss TEMPEST with  the private sector.  For
privacy's  sake, this policy must be  changed to a proactive
one.  The NIST should publicize  the TEMPEST ELINT threat to
computer security  and  should set  up a  rating system  for
level  of  emanations  produced  by  computer   equipment.31

Further,  legislation  should  be  enacted  to  require  the
labeling  of  all computer  equipment    with  its level  of
emanations and whether it is TEMPEST Certified.  Only if the
public  knows of the problem  can it begin  to take steps to
solve it.

Title III makes  possession  of  a  surveillance   device  a
crime,  unless  it   is  produced  under  contract   to  the
government.  This means that  research into surveillance and
counter-surveillance   equipment   is  monopolized   by  the
government and a  few companies working under  contract with
the government.   If TEMPEST eavesdropping  is criminalized,
then possession of TEMPEST ELINT equipment will be criminal.
Unfortunately,this  does  not  solve the  problem.    Simple
TEMPEST  ELINT equipment is  easy to make.   For  just a few
dollars  many  older  television  sets  can be  modified  to
receive  and  reconstruct EMR.    For  less than  a  hundred
dollars a more  sophisticated TEMPEST ELINT receiver  can be
produced32.

The  problem  with  criminalizing  the  possession   of TEM-
PEST  ELINT  equipment  is  not just that the law  will have
little effect on the use of such equipment, but that it will
have a  negative effect  on counter-measures  research.   To
successfully   design   counter-measures  to   a  particular
surveillance  technique  it  is  vital  to have  a  complete
empirical  understanding   of  how  that   technique  works.
Without  the right  to  legally  manufacture a  surveillance
device there is no possible way for a researcher to have the
knowledge to  produce an effective  counter-measures device.
It  is  axiomatic:  without  a  surveillance device,  it  is
_________________________
certify.  Since  the standard is classified,  the  con-
tractors  can  not  sell  the  equipment  to non-secure
governmental agencies or the public.  This prevents re-
verse  engineering  of  the  standard  for its physical
embodiment, the  Certified equipment.   By   preventing
the    private   sector   from   owning    this   anti-
eavesdropping  equipment,   the  NSA  has   effectively
prevented   the them from protecting the information in
their computers.




                        June 7, 1990





                           - 13 -


impossible to test a counter-measures device.

A number of  companies produce  devices to measure  the ema-
nations  from  electrical  equipment.  Some of these devices
are  specifically   designed  for   bench  marking   TEMPEST
Certified equipment.  This does not  solve the problem.  The
question   arises:  how  much   radiation  at  a  particular
frequency is compromising?   The current answer is  to refer
to NACSIM  5100A.   This document  specifies the  emanations
levels suitable  for Certification.   The  document is  only
available  to  United States  contractors  having sufficient
security  clearance  and  an  ongoing  contract  to  produce
TEMPEST Certified computers  for the  government.   Further,
the correct  levels are specified by the NSA and there is no
assurance that, while these levels are sufficient to prevent
eavesdropping by unfriendly operatives,  equipment certified
under NACSIM 5100A  will have levels  low enough to  prevent
eavesdropping by the NSA itself.

The  accessibility  of  supposedly  correct  emanations lev-
els   does   not  solve  the  problem of  preventing TEMPEST
eavesdropping.     Access   to  NACSIM   5100A  limits   the
manufacturer to selling the equipment  only to United States
governmental  agencies  with  the  need  to  process  secret
information.33  Without  the right to possess  TEMPEST ELINT
equipment  manufacturers  who  wish to  sell  to  the public
sector  cannot determine what a safe level of emanations is.


_________________________
30.  Previously the Bureau of Standards.   The NIST  is
a division of the Commerce Department.
31.  In this case computer equipment would include  all
peripheral  computer equipment.  There is no use is us-
ing a TEMPEST Certified computer if the printer or  the
modem are not Certified.
32.  The  NSA  has tried  to  limit  the   availability
of  TEMPEST  information  to  prevent the spread of the
devices.
     For a discussion of the  First Amendment and prior
restraint  See,  e.g.  The United  States of America v.
Progressive,    Inc.   467   F.Supp   990   (1979,   WD
Wis.)(magazine  intended  to  publish plans for nuclear
weapon; prior   restraint  injunction   issued),   reh.
den.   United  States v. Progressive  Inc. 486 F.Supp 5
(1979,  WD Wis.), motion   den   Morland   v.  Sprecher
443   US   709  (1979)(mandamus), motion denied  United
States  v. Progressive,  Inc. 5  Media L  R (1979,  7th
Cir.),  dismd. without op. U.S. v. Progressive, Inc 610
F.2d 819 (1979, 7th Cir.); New York Times, Co. v.   Un-
ited     States,     403     U.S.     713    (1971)(per
curium)(Pentagon  Papers   case:  setting  forth  prior
restraint  standard   which  government  was unable  to
meet); T.  EMERSON, THE SYSTEM  OF FREEDOM OF   EXPRES-



                        June 7, 1990





                           - 14 -


Further  those manufacturers  with  access to  NACSIM  5100A
should  want  to  verify that  the  levels  set  out in  the
document are, in  fact, low enough to  prevent interception.
Without an actual  eavesdropping device with which  to test,
no   manufacturer  will   be  able   to  produce   genuinely
uncompromising equipment.

Even if the  laws  allow  ownership  of   TEMPEST  Certified
equipment by the public, and even  if the public is informed
of  TEMPEST's   threat  to  privacy,   individuals'  private
information will not necessarily  by protected.  Individuals
may choose  to protect  their own  information on  their own
computers.  Companies  may choose  whether to protect  their
own  private  information.    But  companies that  hold  the
private information of  individuals must  be forced to  take
steps to protect that information.

In  England the   Data   Protection   Act   198434   imposes
sanctions   against   anyone   who   stores   the   personal
information35 on  a computer  and fails  to take  reasonable
measures to prevent disclosure of that information.  The act
mandates that  personal  data  may  not  be  stored  in  any
computer  unless  the  computer bureau  or  data  user36 has
registered under the  act.37    This provides for a  central
registry  and  the tracking  of  which companies  or persons
maintain databases of personal information.   Data users and
bureaux must  demonstrate a  need and  purpose behind  their
possession of personal data.

The  act provides  tort remedies   to  any  person   who  is
_________________________
SION  (1970); Balance  Between Scientific  Freedom  and
NAtional    Security,     23    JURIMETRICS     J.    1
(1982)(current   laws  and  regulations limiting scien-
tific and  technical expression exceed the   legitimate
needs  of national security); Hon. M.  Feldman, Why the
First  Amendment is  not  Incompatible   with  National
Security,   HERITAGE   FOUNDATION  REPORTS  (Jan.   14,
1987).  Compare Bork,   Neutral  Principles   and  Some
First  Amendment  Problems,   47  IND.  L. J. 1  (First
Amendment applies only to  political speech); G.  Lewy,
Can  Democracy   Keep  Secrets,  26   POLICY  REVIEW 17
(1983)(endorsing draconian secrecy laws  mirroring  the
English system).
33.  For  example, the  NSA has  just recently  allowed
the  Drug Enforcement Agency  (DEA) to purchase TEMPEST
Certified  computer  equipment.     The   DEA    wanted
secure computer  equipment because wealthy  drug  lords
had  were   using  TEMPEST   eavesdropping equipment.
34.  An  Act  to  regulate  the  use of   automatically
processed  information  relating to individuals and the
provision of services in respect of such information.
Data Protection Act 1984, Long Title.




                        June 7, 1990





                           - 15 -


damaged by disclosure  of the  personal data.38   Reasonable
care to  prevent the  disclosure is  a  defense.39   English
courts have not  yet ruled what  level of computer  security
measures  constitute  reasonable   care.    Considering  the
magnitude of invasion possible with  TEMPEST ELINT it should
be  clear by  now  that  failure  to use  TEMPEST  Certified
equipment is prima facie unreasonable care.

The Remedies section of  the   act  provides  incentive  for
these entities  to provide  successful protection  of person
data from disclosure or illicit access.   Failure to protect
the data will result  in monetary loss.  This may  be looked
at from the economic efficiency  viewpoint as allocating the
cost of  disclosure  the persons  most  able to  bear  those
costs, and also most able to prevent disclosure.  Data users
that  store  personal  data   would  use  TEMPEST  Certified
equipment as part of their computer security plan, thwarting
would-be eavesdroppers.


_________________________
35.  "Personal data" means data  consisting of informa-
tion  which relates to a  living individual who  can be
identified from  that information  (or  from  that  and
other  information in the possession of the data user),
including any  expression of opinion about the  indivi-
dual  but not any  indication of the intentions of  the
data user in respect of that individual.
Data Protection Act 1984   1(3)
36.  "Data user" means  a person  who holds data,   and
a  persons "Holds" data if --
(a) the data form part of  a collection  of  data  pro-
cessed  or intended to be processed by  or on behalf of
that person  as mentioned  in  subsection   (2)  above;
[subsection  (2) defines "data"] and
(b) that person (either  alone or jointly or in  common
with other persons)  controls the contents  and use  of
the  data comprised in the collection; and
(c) the data are in the form  in which they  have  been
or  are  intended to be processed as mentioned in para-
graph (a) above or (though not  for the time being   in
that  form)  in   a form into which they have been con-
verted after being so processed and  with  a  view   to
being   further   so  processed  on  a subsequent occa-
sion.
Data Protection Act   1(5).
37.  Data Protection Act 1984,   4,5.
38.  An individual who is the subject of personal  data
held  by a data user... and who  suffers damage by rea-
son of  (1)(c) ... the disclosure of the  data, or  ac-
cess  having  been  obtained to  the data without  such
authority as  aforesaid shall  be entitled  to  compen-
sation  from  the data  user... for any  distress which
the individual has  suffered  by  reason of   the   ...



                        June 7, 1990





                           - 16 -


The Data Protection  Act 1984  allocates risk to  those  who
can  bear   it  best  and provides an  incentive for them to
keep other  individuals' data private.   This act  should be
adopted by the United States as part of a full-spectrum plan
to combat TEMPEST eavesdropping.  Data users are in the best
position  to  prevent  disclosure  through  proper  computer
security.   Only  by  making  them  liable for  failures  in



                           - 16 -
77777777777security  can  we  begin  to  rein in TEMPEST ELINT.  Do not
criminalize  TEMPEST ELINT.  Most crimes  that TEMPEST ELINT
would  aid, such a insider trading, are already illegal; the
current laws are adequate.




                           - 16 -
777777777The  National Institute  of Standards and  Technology should
immediately begin  a program  to educate the  private sector
about TEMPEST.  Only if  individuals are aware of the threat
can  they  take  appropriate precautions  or  decide whether
any precautions are necessary.




                           - 16 -
7777777777Legislation   should  be  enacted   to  require   all  elec-
tronic  equipment   to  prominently   display  its level  of
emanations  and  whether  it  is   TEMPEST  Certified.    If
individuals are to choose to protect themselves they must be
able  to  make  a  informed   decision  regarding  how  much
protection is enough.




                           - 16 -
77777777777TEMPEST Certified equipment  should  be   available  to  the
private   sector.    The  current   ban on  selling to  non-
governmental  agencies  prevents  individuals  who  need  to
protect information from having the technology to do so.




                           - 16 -
777777777Possession of  TEMPEST ELINT equipment should  not  be  made
illegal.    The   inherently   passive  nature   and  simple
design  of  TEMPEST ELINT  equipment  means that  making its
possession illegal will  not deter crime;  the units can  be
easily manufactured and are impossible  to detect.  Limiting
their   availability   serves   only   to   monopolize   the
countermeasures research, information, and equipment for the
government;   this   prevents   the  testing,   design   and
manufacture of counter-measures by the private sector.




                           - 16 -
77777777777777Legislation mirroring  England's Data Protection   Act  1984
should be  enacted.  Preventing disclosure  of personal data
can  only be  accomplished  by giving  those companies hold-
ing  the  data  a  reason to protect  it.  If data users are
held liable for  their failure  to take reasonable  security
precautions  they  will begin  to  take  reasonable security
precautions,  including   the  use   of  TEMPEST   Certified
equipment.



9  []         Respectfully submitted,

        Christopher  J.   Seline           cjs@cwru.cwru.edu
        cjs@cwru.bitnet






































9


                        June 7, 1990