Violent Crime and Digital Evidence

Challenges Violent crimes are challenging to investigate – the severe behavior that is involved, – the complexity of formative events and – relationships. That is to say, these types of crimes do not happen in a vacuum. – CASE EXAMPLE (MARYLAND, 2010) – After arresting Jason Scott for allegedly killing a mother and daughter, Delores and Ebony Dewitt, police searched his home and found various sources of digital evidence. The digital evidence included a memory stick with photographs

The Role OF Computers IN Violent CRIME )Cybertrails – Computers may contain useful information about the Internet activities of individuals involved in a violent crime. For instance, communications between the victim and offender, especially in cases of intimate homicide. the planning and commission of the crime. – Data from Internet service providers used by the victim or suspect can also help determine their activities around the time of the crime, their whereabouts, and their identity. serial murderer Maury Travis was tracked down using the IP address he used when accessing an online map Web site.

CASE EXAMPLE (NEW HAMPSHIRE, 2001) Two teenagers, stabbed and killed professors in their home.,had purchased the murder weapons, SOG Seal 2000 knives, on the Internet. Police tracked purchases of such knives and interviewed the teen- agers but did not initially suspect them. After being interviewed by police, the teenagers contacted each other over Instant Messenger and agreed to flew to California. Police were ultimately able to link the murder weapon to teenagers, and apprehended them.Both received a life sentenceand 25 years to life.

Figure 1.1 Copyright © 2011 Academic Press Inc. FIGURE 10.1 Diagram depicting potential sources of digital evidence linking the victim of a violent crime with the offender and crime scenes.

THE ROLE OF MOBILE DEVICESIN VIOLENT CRIME Mobile devices may contain – information about communications – audio or video recordings relating to an offense. – location of victims and suspects at key times. – In one homicide case, Joe O’Reilly claimed that he was at work when his wife was killed but his cell phone location showed him traveling from work to the scene of the crime and then returning to work. His location and the direction he was moving were confirmed by digital evidence obtained from CCTV cameras.

THE ROLE OF PERSONAL COMPUTERS IN VIOLENT CRIME A victim’s computer may contain – a diary – frequently retain sent and received s that offer a unique view into his/her personal life. – can include evidence of criminal activity, – and clandestine relationships that even friends and family do not know about. Digital evidence may be useful for locating a missing person when it contains clues of whom she communicated with and where she might have gone.

THE ROLE OF PRIVATE NETWORKS IN VIOLENT CRIME privately owned networks can also be a rich source of information Information gathered in digital form by other businesses such as – banks, – telecommunication providers, – credit card companies, and – electronic toll collection systems – can reveal a significant amount about an individual’s whereabouts and activities. CASE EXAMPLE (CHESHIRE, UNITED KINGDOM) In the U.K. case involving Dr. Harold Shipman, changes he made to computerized medical records on his medical office computer system were instrumental in convicting him of killing hundreds of patients. Shipman used to maintain patient records, investiga- tors found that the program kept an audit trail, recording changes made to patient records. This audit trail indicated that Shipman had lied about patients’ symptoms and made backdated modifications to records to conceal the mur- ders. Had the investigators accepted the patient records without digging deeper into their authenticity, they would have missed this key piece of evidence about the cover- up attempt.

THE ROLE OF INTENT AND MOTIVE IN VIOLENT CRIME In addition to providing concrete leads, a murderer’s computer or mobile device may disprove offender statements, show his intent to commit a crime, and uncover evidence of staging such as a fake suicide note created after the victim’s death. For instance, Reverend William Guthrie was sentenced to life in prison partly on the basis of digital evidence showing that he used a computer to search online for ways to kill his wife and to fabricate a suicide note sev- eral months after her death

PROCESSING THE DIGITAL CRIME SCENE wear nitrile gloves to prevent their fingerprints from transferring onto objects and to protect their skin from hazardous substances Authorization(searches with/without a warrant.) Preparation: Make a Plan, Follow the Plan Crime Scene Survey and Documentation – (Overlooked Evidence :During an internal investigation in a large corporation, one server that had been preserved on a rack of a dozen other systems was central to the investigation. The server had been put in place without the knowledge of upper management and was being used against corporate policy to monitor online activities of various employees.) Enterprise Networks as Evidence – to collect the content of network activities and telephone conversations – care must be taken not to put too much trust in those who run the systems for a number of reasons, including the following: They may not have a forensic background, leading to lost or tainted evidence. They have interest in protecting the organization from liability or negative press They could be a friend of the victim and try to protect the victim’s data. They may be the offender.

INVESTIGATIVE RECONSTRUCTION Pulling all evidence together and letting it speak for itself. Consider alternative explanations for a given piece of evidence rather than jumping to a conclusion on the basis of personal bias or past experience.

INVESTIGATIVE RECONSTRUCTION Offender Behavior – to look for behaviors that leave digital traces. Victimology – Victimology is the assessment of the victim as they relate to the offender, the crime scene, the incident, and the criminal justice system. Crime Scene Characteristics – crime scenes fall into two categories— – Primary: where the violent offense occurred and – Secondary: where the victim was abducted and where the offender discarded clothes, weapons, and digital devices. Computers and mobile devices are treated as secondary crime scenes in violent crime investigations