A jury convicted Mr. DuBoise of first-degree murder and attempted sexual battery in 1985, and a judge sentenced him to death. In 1988, the Florida Supreme Court changed the sentence to life in prison.
In 2007, Mr. DuBoise filed a motion to have DNA from his case tested, but the evidence admitted at his trial had been destroyed in 1990, and Mr. DuBoise’s motion was denied, prosecutors said.
Then, last September, the Innocence Project asked Mr. Warren’s office, which had created a Conviction Review Unit in 2018, to examine Mr. DuBoise’s case.
A review by the unit and the Innocence Project found that the injury on Ms. Gram’s cheek was not a bite mark and that the jailhouse informant who testified against Mr. DuBoise was not credible, prosecutors said.
Mr. Warren said that the scientific community, including the National Academy of Sciences, had rejected the type of bite-mark analysis used in Mr. DuBoise’s case. The expert who testified that it was Mr. DuBoise’s bite has since renounced similar evidence in other cases, Mr. Warren said. And a dental expert cited by the Innocence Project found that the injury on Ms. Grams’s cheek was not a bite mark at all, Mr. Warren said.
The Innocence Project also discovered “significant inconsistencies” in the jailhouse informant’s testimony, and his sentence was reduced after he cooperated with investigators, Mr. Warren’s office said.
The DNA test results further discredited the informant because the results did not match Mr. DuBoise, his brother or his friend, whom the informant had implicated in the crime, Mr. Warren said.