Archive for the ‘Criminal Investigation’ Category

Improving line-up procedures

July 16, 2018

This article reviews suggested modifications to police line-up procedures designed to reduce mistaken identifications by witnesses, which account for 29% of post-conviction exonerations. Better procedures have been well known for 20+ years and have been endorsed by professional organizations, but not all departments have adopted them. Louisiana recently enacted statewide requirements, with proposals also pending in California, Iowa, and New Mexico.


Where killings go unsolved

June 7, 2018

This article analyzes over 50,000 homicides in U.S. cities, mapping neighborhoods with higher and lower clearance rates. There are variations between cities but also within, with fewer murders solved in low-income minority neighborhoods. Factors seem to include the challenge presented by drug- and gang-related cases, reluctant witnesses, lack of trust in police, and the resources devoted to homicide investigation.

Science rarely solves crime

May 30, 2018

This paper reports an in-depth study of the impact of forensic science on investigation and adjudication. One finding is that lab results rarely contribute to identifying the suspect. Because of limited lab capacity, backlogs, and costs, any forensic analysis usually comes later to confirm other evidence for use at trial or as leverage for plea bargaining. This limits the contribution of science for actual crime solving and contributes to system errors by putting the focus on known suspects rather than on an unfettered search for the facts.

The long hunt for the Golden State Killer

May 29, 2018

The recent arrest of the Golden State Killer resulted from a DNA match through a database of genealogical records. This article discusses why it took several decades to solve the high-profile serial murder cases. DNA and other technology wasn’t available when the crime series began, information sharing among agencies wasn’t always seamless, and some of the cases were thought to have been solved but suspects were later exonerated.

Police vs. prosecutor on transparency

May 26, 2018

This article reports push-back by Phoenix in response to their county attorney asserting control over “when and how police departments should release officer body-cam video and other evidence.” The city says “Transparency is absolutely necessary for the Phoenix Police Department to build and maintain stronger trust relationships” but the prosecutor says statutes and rules govern the release of evidence in ongoing criminal investigations.

Fingerprints before computers

May 25, 2018

Fingerprints have been used for well over 100 years to conclusively identify people, but before computers it was nearly impossible to start with a latent print from a crime scene and match it to an otherwise unknown suspect. This 9-minute public radio segment tells the story of one exception from the 1920s, when a federal fingerprint examiner in DC with a really good memory linked a latent print from a Kansas murder, which was connected to a bank robbery/kidnapping/murders case in Colorado, to a 10-print card submitted following an arrest a year later in California.

Mining social media

April 27, 2018

This article discusses legal and ethical issues connected to police mining of social media. Data from social media have the potential to solve and prevent crimes as well as terror attacks, but many 4th amendment and privacy questions have yet to be sorted out. Also, choices of search terms and phrases can reflect bias and result in police actions that have disproportionate impact on some groups. Among the suggestions is transparency so residents can understand and critique the algorithms and processes that police propose.

Bias in forensic science

April 21, 2018

This brief column describes ways in which the meaning of forensic evidence can be distorted by cognitive and occupational biases. “Bias cascade” occurs when observations and decisions from one stage of the investigation affect later stages that should be independent. “Bias snowball” causes the impact to grow from one stage to the next. These biases may be most likely when investigators and criminalists work from a suspect to the evidence, rather than starting from the evidence, as they should. The “consequence of cognitive biases is that science is misused, and sometimes even abused, in court.”

Cross-deputization in Indian Country

April 12, 2018

Jurisdictional issues have long plagued Indian Country policing, with a confusing combination of laws and court decisions at the tribal, federal, and state levels. Enhancing clarity and improving effectiveness are important since rates of serious crime tend to be high while clearance rates run low, resulting in too much victimization and too little justice. This new publication examines several promising practices, including increased cross-commissioning and cross-deputizing of law enforcement officers in and around Indian Country.

Custom Blackberry CEO busted

March 13, 2018

This article reports a multi-national investigation by the U.S., Canada, and Australia into a company that provided custom Blackberry devices for secure communication within private networks, with encryption and remote “wiping” if a phone was seized by authorities. About 20,000 of the devices are in circulation with a clientele that includes drug cartels and transnational organized crime groups. The company’s CEO was arrested last week.