Fort Lauderdale - A Florida man was released from custody on Thursday after spending 26 years in prison for a rape and murder his lawyer says he didn't commit.

Anthony Caravella was ordered released after a private laboratory test revealed someone else's DNA at the crime scene.

Although it was once considered a rare and remarkable event, a growing number of defendants are being ordered freed from prison as DNA tests continue to uncover evidence of false confessions, shoddy police work, and questionable prosecution tactics.

Mr. Caravella's release on Thursday is conditional, pending further investigation. If the release order becomes permanent he will be the 243rd person freed by DNA evidence nationwide, the 11th in Florida, and the fourth in Broward County.

Seth Miller, executive director of the Innocence Project of Florida, says despite the proven success of such efforts it is becoming increasingly difficult for defense lawyers to pursue DNA testing.

"Across the state of Florida the state is opposing DNA testing more often on the front end, rather than taking a wait and see approach," Mr. Miller says.

"Nobody likes to admit they are wrong," he says.

Prosecutors in the Caravella case have cooperated with defense lawyers in an apparent effort to uncover the truth.

Mr. Caravella was 15 years old in 1983 when detectives questioned him in connection with the murder of Ada Jankowski in nearby Miramar, Fla. Caravella has an IQ of 67 and is considered mentally retarded.

His lawyer, Chief Assistant Public Defender Diane Cuddihy, said in a court motion that Caravella was threatened, beaten, pushed, and slapped by police. He gave police four taped statements and one oral statement. He eventually confessed to the rape and murder and was sentenced to life in prison.

Ms. Cuddihy said the confession was based on improper coercive interrogations that produced unreliable and false admissions by her client. She said detectives asked leading questions. She said even with leading questions, Caravella was unable to give verifying details of the murder and rape that matched crime scene evidence known to the detectives.

The public defender hired a private laboratory to re-test DNA evidence gathered in the case. The results showed someone other than Caravella raped Ms. Jankowski during the murder-rape. In addition, Cuddihy accused police and prosecutors of withholding a key piece of evidence from defense lawyers during Caravella's trial.

The lawyer said the state failed to turn over to defense lawyers an audio tape of a phone conversation between a police detective in the Jankowski case and a man who said he had killed Jankowski with Caravella.

"The audio tape, although delivered and received by the state attorney, was never disclosed to the defendant or his counsel," Cuddihy says in a court filing.

"The newly discovered DNA evidence proves that the defendant did not commit the sexual battery and murder," she writes. "The hidden audio-tape further undermines the reliability of the verdict."

Miller notes that false confessions contributed to a wrongful conviction in about 25 percent of cases where DNA evidence resulted in a defendant's release.

Frequently such confessions result from a combination of coercive interrogation tactics used against a person with mental retardation, he says.