From the moment 4-year-old April Tucker died, Debbie Tucker Loveless and John Harvey Miller told police and prosecutors that she had been mauled by dogs. But in 1989, the couple was convicted of murdering her and sentenced to life in prison.

Four seemingly endless years later, in 1993, the Texas Court of Criminal Appeals overturned their convictions, after a state district judge ruled prosecutors had withheld critical evidence that vindicated the couple.

Between 1989 and 2011, at least 86 Texas defendants including Loveless and Miller had their convictions overturned, according to the National Registry of Exonerations. In an extensive analysis of court rulings, news reports and pardon statements, The Texas Tribune found that in nearly one-quarter of those cases — 21 in total — courts ruled that prosecutors made mistakes that in most instances contributed to the wrong outcome. The wrongfully convicted in those cases spent a combined total of more than 270 years in prison. (See an interactive presentation with details about all the cases.)

In the cases, judges found that prosecutors broke basic legal and ethical rules, suppressing important evidence and witness testimony and making improper arguments to jurors. Despite the courts’ findings of some serious missteps, the State Bar of Texas reports very little public discipline of prosecutors in recent history.

The State Bar does not track discipline of prosecutors separately from other lawyers. But Linda Acevedo, the chief disciplinary counsel for the State Bar who has been at the agency since 1985, said she could recall three prosecutors who were publicly reprimanded. None of the reprimands were related to the 86 wrongful convictions.

“Right now, there is next to no oversight of what prosecutors do,” said Jennifer Laurin, a professor who teaches criminal procedure at the University of Texas School of Law.

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