It was a single sheet of paper containing the lab results of analyst Pamela Fish, written in a tight scrawl. They showed she did not find Willis' blood type in semen recovered from the crime scene.At his 1992 trial, though, Fish had testified her results were "inconclusive," meaning she could neither include nor exclude Willis as a potential source of the semen. Her testimony effectively denied him the scientific evidence that could have undermined the state's case.
The question of who was responsible for Fish's crucial test results not being provided for Willis' trial remains a matter of heated debate.
What is not disputed is that Willis served 8 1/2 years behind bars for a crime he did not commit. The city and Cook County paid him $2.5 million and the state $100,000 to settle his wrongful conviction lawsuit, though no one admitted wrongdoing and the city said Fish followed protocols in her testing.
And Fish's career is in ruins. Earlier this year, the highly touted scientist, who once trained Illinois State Police DNA analysts, was quietly let go.
By her own account, Fish could have redone the tests in the Willis case to clarify the results, and even her bosses still say she should have.
"Was her interpretation one of the possible answers? Yes," James Kearney, Fish's former boss at the state police lab in Chicago, said in an interview. "Should her work have been redone? You know my answer to that--the work needed to be redone."
The behind-the-scenes drama of the Willis case, revealed in documents the Tribune went to court to unseal, provides a rare look inside the often-closed culture of Illinois' crime labs and is a vivid example of how faulty lab practices can help convict the innocent.
Labs are supposed to be where science and the pursuit of justice merge, but too often they are a place where mistakes, omissions and a lack of rigor lead investigators down false trails that end in wrongful convictions. A Tribune investigation has found that across the country, forensic science is being undermined by unproven theories and experts who testify in a misleading fashion.
For years, Fish has been a focus of criticism by defense attorneys and state legislators because her testing has been at the center of two major wrongful conviction cases involving five men, three of whom still have lawsuits pending against her.
But the work and testimony of other Illinois state lab analysts also have been challenged.
Two lab examiners asserted in a 1997 murder trial in Kane County that they could definitively link the defendant to the crime through his lip prints, even though the FBI has never validated the practice.
Two years ago, after a Cook County public defender questioned as misleading a drug analyst's report, lab officials had to step in and clarify policy.
And earlier this month, a DNA analyst pleaded guilty to charges of falsifying thousands of dollars of overtime claims, raising questions about her credibility as a prosecution witness.
Through city attorneys, Fish declined to be interviewed for this article. The city is defending her in two lawsuits involving her testing while she worked at the Chicago Police Department crime lab.
Her supporters say she has been unfairly maligned and held to scientific standards that have rapidly evolved in the years since she completed the disputed Willis tests in 1991. Her testing in that case, for instance, involved serology, a less exact method of identifying potential suspects than current DNA analysis.
"Dr. Fish has never been found to have testified falsely or reported false forensic results," wrote city attorney Thomas Samson in a letter responding to Tribune questions about her work. "Despite this, unproven allegations have ruined the career and reputation of a dedicated public servant and a smart, educated, forward-thinking scientist."
But even Fish's current and former bosses at the lab said in interviews that there were times she fell short. The commander of the Illinois state crime labs, Michael Sheppo, echoed Kearney's criticism that she should have retested the evidence in the Willis case.