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Microscopic hair 



Microscopic hair comparison or analysis has been used as a forensic science tool for over fifty years.  In criminal investigations, analysts examine the hairs found at a crime scene under a microscope and try to determine if it matches with those of the suspect. Initially, this forensic method was used to narrow the field of suspects. However, by the 1970's, microscopic hair analysis began to claim a stronger standard, going as far as using hair comparison for scientific proof of a specific persons' presence at a crime scene or other place of interest. 


With the advent of DNA technology, many began to question the reliability of microscopic hair comparison. In 2015 the Department of Justice and the FBI formally acknowledged that 26 out of 28 FBI analysts on the hair analysis unit offered flawed evidence for nearly every criminal trial in which they testified during a two-decade period prior to the year 2000.  Further, the review (which was conducted in part by the FBI) proved that over 10% of those same cases were directly contradicted DNA analysis of the hairs.


To read the FBI press release in full, click here. Additional resources on microscopic hair analysis and faulty forensic science can be found at the bottom of this page in the "Additional Resources" section.


What is Microscopic hair Comparison?

Richard Danzinger

Chris Ochoa

FREEDOM STORY: Richard Danzinger

Richard Danzinger was only 18 years old when he was convicted of the sexual assault of Nancy DePriest, based on the faulty science of microscopic hair comparison.  


Nancy DePriest was working the night shift at an Austin, Texas Pizza Hut location when she was shot and sexually assaulted.  In the days following her death, Richard Danzinger and his roommate Christopher Ochoa, were seen at the restaurant eating pizza and drinking beer. An employee of Pizza Hut recognized the pair as employees of a different Pizza Hut location and reported their behavior as suspicious, stating that they seemed to be "raising toasts" in DePriest's honor.


Police believed that the perpetrator who entered Pizza Hut on the night of the crime must have had a master key, and thus identified Danzinger and Ochoa as the lead suspects of the attack. During the investigation, Danzinger denied any involvement with the crime and claimed to be at his girlfriend's house at the time that it occurred. Ochoa, who was interrogated separately, confessed that Danzinger had shot DePriest and that the both of them raped her.  Ochoa, who faced the death penalty, accepted a plea deal in which he agreed to testify against Danzinger and to plead guilty.  However, at the trial, Ochoa contradicted his confession and stated that he himself shot DePriest because she recognized him. 


Despite Ochoa's inconsistent testimony, which was later believed to be a false confession, Danzinger was convicted of the crime based on faulty microscopic hair analysis.  At the scene of the crime, investigators found a pubic hair near the body of Nancy DePriest which they claimed "was consistent with Danzinger's hair." All DNA evidence was inconclusive, and the similarity of hair characteristics was the only evidence linking Danzinger to the crime.  Both he and Ochoa were sentenced to life in prison.


Eight years later in 1998, Texas Governor George W. Bush received a letter from an inmate by the name of Achim Josef Marino, who was serving three life sentences for aggravated robbery and who had renewed his spirituality while incarcerated.  In the letter, Marino wrote that his conscious sickened him because he did "this awful crime" and he acted alone. Marino's confession was later corroborated by physical evidence.  DNA from the rape kit as well as mitochondrial DNA from the pubic hair was retested in 2000, both of which matched the DNA of Marino. Keys to the Pizza Hut, as well as bank pouches and a pistol, were also found at Marino's parent's home. 



In February 2002, with the help of the Wisconsin Innocence Project, both Danzinger and Ochoa's convictions were overturned and they were released from prison after serving 12 years of their life sentence.  Danzinger was attacked by a fellow inmate while in prison and suffered a brain injury, resulting in permanent brain damage. Both men filed lawsuits against Travis County and the City of Austin for their wrongful convictions.  Danziger received $9 million from Austin, $1 million from Travis County and $500,000 from Ochoa for wrongfully implicating him in the crime. Danziger also received $250,000 in state compensation. Ochoa received $5.3 million from the City of Austin.

additional resources

Click on the links below to download additional resources that highlight the issues with microscopic hair comparison.

FBI Director Comey's Letter to Additional Governers on State Reviews

Microscopic Hair Comparison Infographic

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