Computer Forensics-New Vistas
In Evidence Technology
Sharique M. Rizvi (shariq@iiita.ac.in)
Dr. Madhvendra Misra (madhvendra@iiita.ac.in)
Faculty, IIIT A
Abstract
The paper explores the issues related to the relevance of a
complex area of practice in field of cyber crimes, which has
given new dimensions to the evidence and evidence related laws.
Electronic evidence and their collection presentation, and testing
have opened up a challenge to judiciary for its appropriate
interpretation and assortment with valid sections of competent
laws. The prevalence of cyber crime in digitalized world and
has been scrutinize under the ambit of hi-tech involvement in
computer forensics. The paper checks the procedures of identification
of the source of electronic evidence, search and seizure, precaution
to maintain the sanctity of the original evidences, maintaining
and cross checking the integrity of the evidence collected.
Collection and classification procedures and also throws light
on process of presenting the evidence insuring it to be considered
as best in the court of law.
Key words:
Computer Crime; Electronic Surveillance & Evidence; Computer
Forensics; Search and Seizer
Introduction
Law is said to be the set pattern of desirable conduct for
individuals and groups living in system. It pertinence is held
and up held only by the virtue of time and the association of
subjects to formalized geographical bounders. With changes of
time culture and requirements the legal interpretation and their
scope has found new meanings. With the advent of the third revolution
and mass digitalization of the world the legal ambit and prospective
has increased its cover on the virtual environment. The dynamics
of the environment and the changes, which have occurred, has
not affected the soul of law and legislation, which embodied
in it self the cause to “to support and reinforce belief in
law of the land and the civic society.” In the change prospective
of time and scope wherein the consistency and association with
a formal geographical boundary should be considered as a shortcoming
in the capability of law to provide relief to affected parties.
The challenge, which the legal system faces at hand of innovative
technologies like Computers, Internet and others is immense
and effects the capability of the legal system largely. Although
the judiciary empowered by constitution and other legislations
updated and upgraded from time to time has been discharging
its functions effectively, there are still avenues and challenges
to which Science and Technology has to cater and provide solutions.
The judicial process specifically in consideration with the
cyber world involves issues like crime accomplished and abetted
through electronic or digital devices, resulting into a complex
array of investigative and supportive activities. Which formally
create a chain of process involving classification of the essential
unlawful act (computer crime), preventive and post occurrence
surveillance (electronic surveillance), extraction of useful
information from used devices to unfold the act of crime (computer
forensics) and finally enabling presentation in the competent
court of law. Where:
A Computer Crime is a crime committed with
the aid of, or directly involving, a data processing system
or network , with crime and viruses and hacking reportedly reaching
epidemic proportions. The areas of greatest impact are laptop
theft, data or network sabotage, virus and Trojan infection,
computer fraud, denial of service attacks and excessive network
resource consumption through external scams.
Electronic Surveillance and Prosecution
Electronic Surveillance is
an invaluable tool for fighting digital crime, investigating
agencies cites many instances where criminal activities were
either subverted, or if crimes were perpetrated, those responsible
were apprehended as a result of electronic surveillance by law
enforcement agencies.
Computer forensics is defined throughout
the paper as the use of an expert to preserve, analyze, and
produce data from volatile and non-volatile media storage. This
is used to encompass computer and related media that may be
used in conjunction with a computer as electronic evidence in
a court of law it involves obtaining and analyzing digital information
for use as evidence in civil, criminal or administration cases
it is the scientific examination and analysis of data held on,
or retrieved from, computer storage media in such a way that
the information can be used as evidence in a court of law.
Practices engaged in by law enforcement officers in order to
gain sufficient evidence to ensure the arrest and conviction
of an offender. The latitude allowed police and other law enforcement
agents in carrying out searches and seizures varies considerably
from country to country
Search and Seizure Search and seizure of digital
evidence is the first process that is often disputed. If it
is not completed properly, the defense or prosecution's evidence
may not be admitted. An illegal search and seizure or improper
methodology employed during search and seizure can negatively
affect the admissibility of the evidence
A unique issue with computer forensics search and seizure centers
on the source of the items in the warrant or in verbal/written
affirmation, when a warrant is not needed (e.g., open view resulting
in a search and seizure). For instance, when a computer has
the power turned off, the data in volatile media storage, for
technical purposes, is virtually impossible to reconstruct.
In pre-digital crimes, electricity was not a major factor in
the ability to execute a proper search and seizure. i.e. Volatile
media storage. Aaron Caffrey, the defendant, was arrested under
the suspicion of launching a denial of service attack against
the Port of Houston 's systems on September 20, 2001 . The defense
argued that the Trojan was installed on the defendant's computer
by the others who wanted to frame him for the attack The Trojan
launched the attack from the defendant's computer but the defendant
was not aware of the attack. The forensics examination showed
that there was no sign of a Trojan, only attack tools on the
computer, but could not rule out that a Trojan may have been
in volatile storage media (random access memory). The jury unanimously
decided that the defendant was not guilty.
Though courts may grant a search and seizure warrant, law enforcement
may ask individuals for verbal or written consent searching
and seizing items. However, the voluntary nature of consent
may vary. In Williford v. Texas , the appellant complained that
the search and seizure of his computer was illegal. The appellant
contended that his consent to the search and seizure was tainted
and, as there was no warrant, there was no probable cause. The
judge dismissed the claim. In U.S. v. Habershaw, the issue was
whether the officers involved had the right to search and seize
the computer, and if the defendant was capable of giving consent.
The defendant argued that the warrant went “overboard.” The
defendant gave verbal permission for the officers to operate
his computer after the defendant stated the possible location
of contraband child pornography images on the computer. Searching
and seizing computers raises unique issues for law enforcement
personnel that will influence the government's search and seizure
decisions. Searching or seizing computers, not referring only
to the CPU (Central Processing Unit) but it consists of input
(e.g., a keyboard or mouse) and output (e.g., a monitor or printer)
devices. These devices, known as "peripherals,"' are
an integral part of any "computer system." Failure
to more specifically define the term "computer" may
cause misunderstandings. Having probable cause to seize a "computer"
does not necessarily mean there is probable cause to seize the
attached printer.
Hardware "The physical components or
equipment that makes up a computer system....". Examples
include keyboards, monitors, and printers.
Software "The
programs or instructions that tells a computer what to do."
This includes system programs, which control the internal operation
of the computer system such as Disk Operating For search
and seizure purposes, unless the text specifically indicates otherwise,
the term "computer" refers to the box that houses the
CPU, along with any internal storage devices such as internal
hard drives and internal communications devices such as an internal
modem or fax card. It is important to remember that computer systems
can be configured in an unlimited number of ways with assorted
input and output devices. In some cases, a specific device may
have particular evidentiary value.
“A bookie who prints betting
slips, the printer may constitute valuable evidence; in others,
it may be the information stored in the computer that may be important.
In either event, the warrant must describe, with particularity,
what agents should search for and seize” . The computer system
may be a tool of the offense. This occurs when a defendant to
commit the offense actively uses the computer system. For example,
a counterfeiter might use his computer, scanner, and color printer
to scan currency and then print money. Second, the computer system
may be incidental to the offense, but a repository of evidence.
For example, a drug dealer may store records pertaining to customers,
prices, and quantities delivered on a personal computer, or a
blackmailer may type and store threatening letters in his computer.
In each case, the role of the computer differs. It may constitute
"the smoking gun" (i.e., be an instrumentality of the
offense), or it may be nothing more than an electronic filing
cabinet (i.e., a storage device). In some cases, the computer
may serve both functions at once. Hackers, often use their computers
both to attack other computer systems and to store stolen files.
In this case, the hacker's computer is both a tool and storage
device. By understanding the role that the computer has
played in the offense, it is possible to focus on certain key
questions: Is there probable cause to seize hardware?
Is there probable cause to seize software?
Is there probable cause to seize data? Where will
this search be conducted? The principles of
Fourth
Amendment, Constitution of United States of
Americas apply to computer searches, and traditional
law enforcement techniques may provide significant evidence of
criminal activity, even in computer crime cases. To determine
whether an individual has a reasonable expectation of privacy
in information stored in a computer, it helps to treat the computer
like a closed container such as a briefcase or file cabinet. The
Fourth Amendment generally prohibits law enforcement from accessing
and viewing information stored in a computer without a warrant
if it would be prohibited from opening a closed container and
examining its contents in the same situation. The questions looming
large in the minds of investigation agency and makers of the law
was aptly answered by the fourth amendment in the US Constitution,
which in principle uphold the integrity of individual privacy
with only certain exceptions giving limited privileges to investigation
and enforcement agencies. The Indian Telegraph Act upholds the
privacy in an individual significantly limiting surveillance and
seizer of electronic information only under exception of affecting
public safety and tranquility. Whereas incases of terrorist and
anti national activities individual privacy seizes to exist.
Provisions in Indian Telegraph Act
The Indian Telegraph Act authorizes the surveillance of communications,
including monitoring telephone conversations and intercepting
personal mail, in case of public emergency or "in the interest
of the public safety or tranquility." Every state government
has used these powers. The Union Government also uses the powers
of the Indian Telegraph Act to tap phones and open mail. The
Indian Telegraph Act of 1885 authorizes the surveillance of
communications, including monitoring telephone conversations
and intercepting personal mail, in cases of public emergency,
or "in the interest of the public safety or tranquility."
The central Government and every state government used these
powers during the year. Although the Telegraph Act gives police
the power to tap phones to aid an investigation, they were not
allowed to use such evidence in court; however, under POTA and
the (UAPA) Unlawful Activities Prevention Act such evidence
was admissible in terrorist cases, and some human rights activists
noted that the new UAPA Ordinance confers additional powers
on police to use intercepted communications as evidence in terrorism
cases. While there were elaborate legal safeguards to prevent
police from encroaching on personal privacy, there were no such
protections in terrorist cases.
Electronic Surveillance and the Fourth Amendment
The Olmstead Case.
—With the invention of the microphone, the telephone, and the
dictograph recorder, it became possible to ‘‘eavesdrop'' with
much greater secrecy and expediency. Inevitably, the use of
electronic devices in law enforcement was challenged, and in
1928 the Court reviewed convictions obtained on the basis of
evidence gained through taps on telephone wires in violation
of state law. On a five-to-four vote, the Court held that wiretapping
was not within the confines of the Fourth Amendment. Chief Justice
Taft, writing the opinion of the Court, relied on two lines
of argument for the conclusion. First, inasmuch as the Amendment
was designed to protect one's property interest in his premises,
there was no search so long as there was no physical trespass
on premises owned or controlled by a defendant. Second, all
the evidence obtained had been secured by hearing, and the interception
of a conversation could not qualify as a seizure, for the Amendment
referred only to the seizure of tangible items. Furthermore,
the violation of state law did not render the evidence excludible,
since the exclusionary rule operated only on evidence seized
in violation of the Constitution.
The Berger and Katz
Cases. —In Berger v. New York
, the Court confirmed the obsolescence of the alternative
holding in Olmstead that conversations could not be
seized in the Fourth Amendment sense. Berger held unconstitutional
on its face a state eavesdropping statute under which judges
were authorized to issue warrants permitting police officers
to trespass on private premises to install listening devices.
The warrants were to be issued upon a showing of ‘‘reasonable
ground to believe that evidence of crime may be thus obtained,
and particularly describing the person or persons whose communications,
conversations or discussions are to be overheard or recorded.''
For the five-Justice majority, Justice Clark discerned several
constitutional defects in the law. ‘‘First, . . . eavesdropping
is authorized without requiring belief
that any particular offense has been or is being committed;
nor that the ‘property' sought, the conversations, be particularly
described.
Warrantless ‘‘National Security'' Electronic Surveillance.
—
In Katz v. United States , Justice White sought to
preserve for a future case the possibility that in ‘‘national
security cases'' electronic surveillance upon the authorization
of the President or the Attorney General could be permissible
without prior judicial approval. The Executive Branch then asserted
the power to wiretap and to ‘‘bug'' in two types of national
security situations, against domestic subversion and against
foreign intelligence operations, first basing its authority
on a theory of ‘‘inherent'' presidential power and then in the
Supreme Court withdrawing to the argument that such surveillance
was a ‘‘reasonable'' search and seizure and therefore valid
under the Fourth Amendment. Unanimously, the Court held that
at least in cases of domestic subversive
investigations, compliance with the warrant provisions of the
Fourth Amendment was required.
The Communications Assistance For Law Enforcement Act
(P.L. 103-414)
An affirmative obligation for telecommunication service providers
to assist the law enforcement community in authorized electronic
intercepts, The Supreme Court in United States v.
New York Telephone ,
In (1977) found that 18 U.S.C. 2518(4) required the federal
courts to compel telecommunication providers to provide “any
assistance necessary to accomplish an electronic interception.”
The question of whether a carrier has any obligation to design
its equipment to facilitate an authorized electronic
surveillance under 8 U.S.C 2518(4) was never litigated. The
Communications Assistance For Law Enforcement Act makes it clear
that the service providers must now consider equipment and system
design as well as the capability to provide
the call content and call Identification information needed
by law enforcement agencies, and the capacity that the law enforcement
agencies need to simultaneously intercept a specified number
of wiretaps. The Act also establishes a process for reimbursing
the service providers for their expenses in meeting law enforcement's
needs. The amendment requires the service provider “furnish
the information, facilities, and technical assistance necessary
to accomplish the interception . . . . .” The amendment further
provides that a cooperating service provider to be compensated
for reasonable expenses incurred in providing such facilities
or assistance.
Requirement 1
Law enforcement agencies require access to the
electronic communications transmitted, or caused to be transmitted,
to and from the number, terminal equipment, or other identifier
associated with the intercept subject throughout the service
areas operated by the service provider served with a lawful
authorization. Law enforcement agencies also require access
to generated call-identifying information necessary to determine
the calling and called parties. Law enforcement agencies will
coordinate delivery of these communications with the service
provider in accordance with requirement for each service area.
Law enforcement agencies require real-time, full-time
monitoring capability for interceptions.
Law enforcement agencies require telecommunications
carriers to make provisions for implementing a number of simultaneous
interceptions.
Law enforcement agencies require telecommunications
carriers to expeditiously provide access to the communications
of the intercept subject.
Requirement 2
Law enforcement agencies require:
- Information from the telecommunications carrier to verify
the association of the intercepted communications with the
intercept subject, and
- Information on the services and features subscribed to by
the intercept subject prior to and during the intercept implementation.
Requirement 3
- Law enforcement agencies require telecommunications carriers
to transmit intercepted communications to a monitoring facility
designated by the law enforcement agency.
- During the intercept period, law enforcement agencies require
that the reliability of the services supporting the interception
at least equals the reliability of the communications services
provided to the intercept subject.
- Law enforcement agencies require that the quality of service
of the intercepted transmissions forwarded to the monitoring
facility comply with the performance standards of the telecommunications
carriers.
Requirement 4
- Law enforcement agencies require the intercept to be transparent
to all parties except the investigative agency or agencies
requesting the intercept and specific individuals involved
in implementing the intercept capability. Law enforcement
agencies require the implementation of safeguards to restrict
access to intercept information.
In the case of a Cyber Crime pursued by the Police "Evidence"
plays a vital part in securing the interests of the Information
Asset owner. The legal requirements and the devices required
for the purpose of collecting judicially acceptable Cyber Evidence.
The necessary amendments were made to the Indian Evidence Act
1872 by the Information Technology Act 2000 (ITA-2000).
In the case of electronic documents produced as "Primary
Evidence", the document itself must be produced to the
Court. However, such electronic document obviously has to be
carried on a media and can be read only with the assistance
of an appropriate Computer with appropriate operating software
and application software. In many cases even in non-electronic
documents, a document may be in a language other than the language
of the Court in which case it needs to be translated and submitted
for the understanding of the Court by an "Expert".
Normally the person making submission of the document also submits
the translation from one of the "Experts". If the
counter party does not accept the "Expert's opinion",
the court may have to listen to another "Expert" and
his interpretation and come to its own conclusion of what is
the correct interpretation of a document. In the case of the
Electronic documents, under the same analogy, "Presentation"
of document is the responsibility of the prosecution or the
person making use of the document in support of his contention
before the Court. Based on his " Reading " of the
documents, he submits his case. This may however be disputed
by the counter party. In such a case, it becomes necessary for
the Court to "Get the document Read by an expert” to
its satisfaction. It is necessary to have some clarity on the
legal aspects of such documents presented to the Court because
most of the court battles are expected to revolve around "Proper
Reading " of the documents and "Possible manipulation
of the documents". In making presentation of an "Electronic
Document", the presenter may submit a readable form of
the document in the form of a "Print Out". Question
arises in such a case whether the print out is”Primary Evidence"
or”Secondary Evidence".
Indian Evidence Act, 1872
The key provisions that are made in Indian Evidence Act relate
to widening of the scope of term document` to include electronic
record. Most importantly, section 65B recognizes admissibility
of computer outputs in the media, paper, and optical or magnetic
form. There are detailed provisions relating to admissibility
of computer output as evidence. New section 73A prescribes procedures
for verification of digital signatures. New Section 85A and
85B create presumption as regards electronic contracts, electronic
records and digital signatures, digital signature certificates
and electronic messages.
- According to Indian Evidence Act, section 65 refers to "Cases
in which secondary evidence relating to documents may be given".
However, the modifications made to this section by ITA-2000
have added Sections 65 A and Section 65 B.
- According to Section 65 A therefore, " Contents of
electronic records may be proved in accordance with the provisions
of Section 65B".
Whether by design or otherwise, Section 65B clearly states
that " Not withstanding anything contained in this (Indian
Evidence Act) Act, any information contained in an electronic
record which is printed on a paper, stored, recorded or copied
in optical or magnetic media produced by a computer called the
Computer Output shall be deemed to be also a document...."
However, for the "Computer Output" to be considered
as admissible evidence, the conditions mentioned in the Section
65 B (2) needs to be satisfied. Section 65B(2) contains a series
of certifications which is to be provided by the person who
is having lawful control over the use of the Computer generating
the said computer output and is not easy to be fulfilled without
extreme care. It is in this context that the responsibility
of the Law Enforcement Authorities in India becomes enormous
while collecting the evidence. In a typical incident when a
Cyber Crime is reported, the Police will have to quickly examine
a large number of Computers and storage media and gather leads
from which further investigations have to be made. Any delay
may result in the evidence getting obliterated in the ordinary
course of usage of the suspect hard disk or the media.
Any such investigation has to cover the following main aspects
of Cyber Forensics, namely,
1. Collection of suspect evidence
2. Recovery of erased/hidden/encrypted data
3. Analysis of suspect evidence
The Best Evidence Rule (US)
The best evidence rule states that to prove the content of
writing, recording, or photograph, the “original” writing, recording,
or photograph is ordinarily required. Agents and prosecutors
occasionally express concern that a mere printout of a computer-stored
electronic file may not be an “original” for the purpose of
the best evidence rule. After all, the original file is merely
a collection of 0's and 1's; in contrast, the printout is the
result of manipulating the file through a complicated series
of electronic and mechanical processes. Fortunately, the Federal
Rules of Evidence have expressly addressed this concern. The
Federal Rules state that, if data are stored in a computer or
similar device, any printout or other output readable by sight,
shown to reflect the data accurately, is an “original”. Thus,
an accurate printout of computer data always satisfies the best
evidence rule. (Holding that AOL Instant Message logs that police
had cut-and-pasted into a word-processing file satisfied best
evidence rule).
Indian Penal Code, 1860
A number of amendments have been made to sections 29, 167,
172, 192, 463, 464 and the like. The key amendment relates to
the widening of term document to include electronic records.
Section 464 now recognizes the concept of digital signature.
The prevalence of mobile digital devices and
there a potential involvement in perpetuating crime and criminal
activities has proven to be a challenge to agencies involved
in electronic surveillance. The problem of tracking with multiple
service providers in different geographical areas has effected
the capability of electronic surveillance systems where as services
like roaming are useful to individuals but are cause of anarchical
situations of investigations
Roaming
When roaming outside of the home service area, law enforcement
requires access to all calls initiated or received by the subject
if the visited service provider has received a lawful request
to activate an intercept, and arrangements have been made for
delivery of the information to the law enforcement-monitoring
site. The visited service provider has no legal obligation to
intercept a cellular target's calls once the subject moves out
of its service area unless it is a call in process. The home
cellular service provider is required to provide access to any
call setup information or call content if access is maintained
in the home area during call delivery to a roaming subject.
Registration Information
When a mobile intercept subject roams into a new service area,
activates his or her mobile unit, and requests service, the
home service providers Home Location Register (HLR) exchanges
information with the new cellular service provider's Visiting
location Register (VLR). When this occurs, law enforcement agencies
require information on the identity of the new service area
requesting the registration information. Law enforcement must
then obtain a lawful authorization to access the call content
and call setup information from the visited service provider.
Conclusion
The inevitable fact that technology is becoming more intertwined
in the daily life of the individual will lead to an increase
in court cases where computer evidence is a vital component.
Because the judicial system is having difficulties in mandating
and interpreting standardization for computer forensics, it
becomes the responsibility of the scientific community to assist
in this endeavor. In the evolution of the Indian challenge to
Cyber Crimes, during the last three years, Police in different
parts of the Country have been exposed to the reality of Cyber
Crimes and more and more cases are being registered for investigation.
However, if the Law enforcement does not focus on the technical
aspects of evidence collection and management, they will soon
find that they will be unable to prove any electronic document
in a Court of Law. Now we have to embark on the next step of
assisting the Law Enforcement in India with suitable Computer
hardware and software that would enhance the quality of "Cyber
Evidence" that can be produced to a court of law in case
of any Cyber Crime. If the process of such collection, recovery
and analysis is not undertaken properly, the evidence may be
rejected in the Court of law as not satisfying the conditions
of Section 65B of the Indian Evidence Act
If the country that suffered damage wants to prosecute a culprit
of foreign nationality, there has to be an extradition treaty
with the country where the hacker is resident. Besides, the
legal framework for proceeding with prosecution is still not
certain. In spite of the extradition treaty, if a law allegedly
broken in a country has no equivalent in the culprit's native
country, there can be no prosecution. In developing countries
including India , the problem is further compounded because
of the lack of training of cops on subjects such as computer
forensics to investigate into cyber crimes or of the adjudicating
officers. This will adversely affect the fight against Cyber
Crime. Unless the police is able to retrieve data from a computer,
they would not be able to deal with the cyber crimes
References:
Indian Information Technology Act 21 of 2000
Indian Evidence Act 1872
Indian Penal Code 1860
Indian Telegraph Act 1885
Forth Amendment Constitution of United States
of America
The Communications Assistance For Law Enforcement
Act (P.L. 103-414), US
- Electronic Surveillance in a Digital Age, July 1995, OTA-BP-ITC-149,
GPO stock #052-003-01418-1