On Tuesday, court records showed that Alvarez's wrongful-convictions unit is seeking a civilian complaints file compiled on Zuley by the independent police review board.
Now his office has established a conviction integrity unit to re-examine the validity of hundreds of convictions.
The Conviction Review Unit has been the most profound reform that Thompson has implemented in his year as district attorney.
His supporters had been mostly pleased, noting that he had created programs like a conviction integrity unit, which examines troubled prosecutions for mistakes.
In January 2011, I created my Conviction Integrity Unit, headed by John O'Mara, a deputy district attorney, to centralize the review of cases like this.
The Conviction Integrity Unit, led by a longtime prosecutor, John O'Mara, already had 14 unrelated cases under review when Mr. Ranta was released in March, said Jerry Schmetterer, a spokesman for Mr. Hynes.
A yearlong investigation into Mr. Ranta's case by the district attorney's Conviction Integrity Unit showed myriad problems, most of them surrounding sloppy and dishonest work by Mr. Scarcella, the lead detective.
Yet John O'Mara, the chief of the district attorney's Conviction Integrity Unit, who says Mr. Scarcella once was one of their busiest homicide detectives, ruled out combing through old cases in search of mistakes by this detective.
"It's a little early to know exactly what the impact of all of this will be," said Barry Scheck, a lawyer and a founder of the Innocence Project, who advised Mr. Vance on the conviction integrity unit.
Supervisors at the district attorney's Conviction Integrity Unit were angered by the discovery of the tape because they felt it was an unauthorized recording because Mr. Ranta already had counsel, a lawyer familiar with the case said.
