Forensic Science Controversies

February 10, 2017 • Volume 27, Issue 6
Are courts relying too much on “junk science”?
By Rachel Kaufman


A technician works at the District of Columbia crime lab. (Getty Images/The Washington Post/Bill O'Leary)
A technician works at the District of Columbia crime lab. Scientists say many forensic techniques, such as bite mark and hair analysis, lack scientific credibility. But prosecutors contend most forensic evidence is reliable and that questioning established methods will make convicting criminals harder. (Getty Images/The Washington Post/Bill O'Leary)

The criminal justice system often relies on forensic evidence to convict or acquit the accused, but some legal experts say many forensic techniques, including bite-mark, ballistic and hair analysis, lack scientific credibility. Even when forensic methods, such as DNA analysis, are scientifically valid, they often have error rates far higher than juries are led to believe. Prosecutors, however, defend forensic methods as reliable and proven by long-standing practice. They worry that if forensics is undermined, convicting criminals will be much harder. Still, both sides agree that the methodology behind many forensic tools can be strengthened by improving the underlying science. In Texas, which was once heavily criticized for weak oversight of forensic practices, a newly reorganized commission is working to improve forensic science in the state. Meanwhile, the FBI is reconsidering its hair-analysis standards following a scandal that triggered a massive post-conviction review of 2,500 cases in which the agency's lab provided sometimes flawed hair-matching evidence.

ISSUE TRACKER for Related Reports
May 27, 2022  Crime in America
Feb. 10, 2017  Forensic Science Controversies
Feb. 05, 2016  Restorative Justice
Jan. 30, 2015  Central American Gangs
Aug. 29, 2014  Transnational Crime
Aug. 09, 2013  Sexual Assault in the Military
Oct. 26, 2012  Mexico's Future
Apr. 20, 2012  Criminal Records and Employment
Apr. 19, 2011  Honor Killings
Sep. 2010  Crime in Latin America
Jul. 16, 2010  Gangs in the U.S.
Jul. 17, 2009  Examining Forensics
Apr. 17, 2009  Wrongful Convictions Updated
Feb. 08, 2008  Fighting Crime
Oct. 11, 2002  Corporate Crime
Apr. 04, 1997  Declining Crime Rates
Dec. 10, 1982  Arson: America's Most Costly Crime
May 07, 1982  Helping Victims of Crime
Mar. 13, 1981  Violent Crime's Return to Prominence
Jul. 15, 1977  Crime Reduction: Reality or Illusion
Jan. 19, 1972  Crime of Rape
Jan. 22, 1969  Street Crime in America
Jan. 17, 1968  Burglary Prevention
Sep. 22, 1965  Compensation for Victims of Crime
Feb. 17, 1965  Criminal Justice and Crime Control
Oct. 18, 1961  Control of City Crime
Jun. 20, 1929  Crime and the Courts
Biology and Life Sciences
Crime and Law Enforcement
Criminal Law Procedure and Due Process
Federal Courts
Science and Politics
Sentencing and Corrections