DNA, crime and law enforcement Personal Genetics Education Project (pgEd) Harvard Medical School

Imagine that there have been a string of murders that appear to be the work of one person. The police have a few leads, but little conclusive evidence. They have DNA, which they believe to be that of the murderer, but it does not match DNA profiles in the criminal databases. The police don’t have enough evidence to arrest the lead suspect, nor do they wish to alert him of their interest in him. Instead, they obtain a warrant to get a sample of DNA from a medical test of the suspect’s adult daughter to compare with DNA from the crime scenes. She does not know about this warrant and, therefore, has not given her consent. 1.Should the police require permission to analyze a DNA sample from the suspect’s child? Why or why not? 2.Take the position of one of the victim’s parents. Do you support this tactic? Why or why not? 3.Take the position of the suspect’s daughter, who has had her DNA secretly tested. Do you support this tactic? Why or why not? Do Now

Photo source: El Dorado Police Department BTK Serial Killer – Dennis Rader Via Wikipedia

Database of DNA profiles that is maintained by law enforcement agencies “Forensic Index” – Database of DNA profiles collected at crime scenes “Offender Index” - Database of DNA profiles collected from people who are arrested or convicted of a crime Big Idea: Compare DNA from the forensic and offender indexes to find matches What is a criminal DNA database?

CODIS (the Combined DNA Index System): The FBI’s program for linking the federal, state and local DNA profiles in a single database. CODIS statistics (as of November 2015): -DNA profiles from over 12,069,150 people are in the “offender index.” -This includes DNA profiles from over 2,173,094 arrestees. -DNA profiles from over 668,285 samples found at crime scenes are in the “forensic index.” Who is in U.S. criminal DNA databases? Data from accessed Jan 28, 2016)

All 50 states collect DNA from convicted felons. 31 states collect DNA from juvenile felony offenders. 42 states collect DNA for some misdemeanor convictions. What types of crimes require a person to provide a DNA sample? Data from

Graffiti Disorderly conduct (ex: protests) “Other” misdemeanors can include: “Graffiti,” Daniel Lee (CC BY-NC-2.0)By MattIndustries, via Wikimedia Commons

Maryland v. King Supreme Court rules 5-4 that DNA can be taken from arrestees Via Wikimedia Commons

The databases are expanding. Some states are broadening the criteria for entry into their offender databases. For example, as of March 2012, New York state includes all people convicted of a misdemeanor. CODIS in 2002: 1.2 million offender profiles CODIS in 2012: 9.7 million offender profiles CODIS in 2015: 11.8 million offender profiles Scientific leaps are creating new opportunities and challenges. Familial searching has generated interest and controversy. What has changed since CODIS was established in 1994? Data from (accessed Jan 28, 2016)

New York Times

Familial searching targets specific family members of people already in a DNA database. Law enforcement agencies collect DNA from a crime scene and compare it to DNA profiles already in the database. If a perfect match is not found, they may look for a partial match with enough markers in common to suggest a familial relationship. If a partial match is found, law enforcement investigate family members further. They may need a DNA sample from the family member to confirm the connection. Sometimes, these samples are collected in secret or from unexpected places, such as a cup, cigarette or pizza crust from the trash. What is familial searching?

Familial searching has helped law enforcement officials to make breakthroughs in some cases, enabling them to catch criminals and exonerate innocent people. Critics say this puts an entire group of people – anyone who has a biological relative with a DNA profile in an offender database – under indefinite genetic surveillance. This technique disproportionately impacts minorities. For example, African-Americans make up 13% of the U.S. population, but 40% of the prison population. Darryl Hunt reacts after being cleared of charges after 19 years in prison for a murder he didn’t commit Winston-Salem Journal Data from and

DNA evidence is powerful; scientific questions still remain “DNA Evidence Can Be Fabricated, Scientists Show” -- Headline from The New York Times, Aug 17, 2009 – Article by Andrew Pollack “Germany’s Phantom Serial Killer: A DNA Blunder” -- Headline from TIME, Mar 27, 2009 – Article by Claudia Himmelreich “Potential for Incorrect Relationship Identification in Forensic Familial Searching Techniques” -- Headline Science Daily, Feb 9, 2012

Slide 3: El Dorado Police Department. Via Wikipedia ( accessed Jan 28, 2016). Slide 7: (left) “Graffiti” by Daniel Lee ( accessed Jan 28, 2016). Available under a Creative Commons Attribution-NonCommercial 2.0 Generic license ( Slide 7 (right) “RNC 2008 day2 Protest” by MattIndustries (Own work) [Public domain], via Wikimedia Commons ( accessed Jan 28, 2016). Slide 8: “Supreme Court US 2010.” Via Wikimedia Commons ( accessed Jan 28, 2016). Slide 10: “I’ve Just Seen a “DNA-Generated” Face” by Heather Murphy, The New York Times, 2015 ( accessed Jan 28, 2016). Slide 12: “Darryl Hunt,” Winston-Salem Journal, File Photo ( v-darryl-hunt/article_ae49b012-25bc-11e4-82c3-001a4bcf6878.html?mode=image, accessed Jan 28, 2016). Image credits