SAVANNAH, Ga. -- A judge has ordered a new trial for a Georgia inmate who has spent 20 years on death row after being convicted of murdering a Wayne County restaurant owner, his wife and their teenage son.

Superior Court Judge Gary McCorvey ruled prosecutors withheld evidence that key witnesses had lied, changed their stories and cut deals with authorities before testifying against Larry Lee of Savannah. McCorvey's order called the trial "fatally flawed" by "prosecutorial acts and omissions."

The ruling also said Lee, 47, of Savannah had an inadequate defense at his trial, where he was represented by a lawyer who had little experience with death penalty cases.

"Not only was the state's evidence in this case 'thin,'" McCorvey wrote in his April 28 order, "but what is more devastating is that trial counsel's preparation for and performance in the penalty phase is even 'thinner,' the investigation and preparation being nonexistent."

District Attorney Stephen Kelley, who was in law school when Lee was prosecuted by his predecessor, criticized the court system for taking "entirely too long" with Lee's appeal. He noted one of two key prosecution witnesses is now dead.

"There's something wrong with a system that takes 21 years to decide if a case needs to be retried," Kelley said.

Kelley said he has asked the state attorney general to appeal the judge's ruling to the Georgia Supreme Court. He said he would hold a new trial if McCorvey's order stands.

A Wayne County jury sentenced Lee to death in 1987 for the murders of a local restaurant owner, 48-year-old Clifford Jones, his wife, 47-year-old Nina Jones, and their 14-year-old son, Jerold.

The three family members were shot to death in their rural southeast Georgia home early in the morning on April 26, 1986. They appeared to have been slain during a burglary. A money bag containing about $1,500 from their restaurant was stolen.

No physical evidence tied Lee to the crime scene. Prosecutors based their case primarily on two witnesses - Lee's sister-in-law, who said she and her husband took part in the robbery with Lee, and a jailhouse snitch who testified Lee had confessed to the murders while they were jailed together in coastal Glynn County.

David Morris, a convicted burglar, told jurors Lee threatened to kill him if he told anyone about the confession. Morris also identified a handwritten note on which he said he had scrawled Lee's threat verbatim after it was made.

But prosecutors failed to disclose to Lee's lawyer, or to the trial jury, that Morris initially told investigators Lee himself had written the note containing the threat. The judge said defense lawyers could have used Morris' lie to undercut his credibility.

Prosecutors also never disclosed that Morris had testified for them as an informant in other criminal trials, the ruling said, or that his cooperation in Lee's case won Morris a transfer from a state prison to a more comfortable county jail.

Sherry Lee, the wife of Lee's brother, agreed to testify against him after a Georgia Bureau of Investigation agent told her the GBI had learned they committed the crimes.

McCorvey's ruling says Sherry Lee's initial statements to authorities differed in key respects to her testimony at Larry Lee's trial. Her prior statements were never made available to Larry Lee's lawyer, who could have used them to discredit her on cross-examination, the judge ruled.

Part of Sherry Lee's testimony was that Larry Lee and her husband, Bruce Lee, stole guns - including an antique shotgun - from Clifford Jones' home. But prosecutors, the judge wrote, never disclosed to the defense or the jury that investigators found no guns missing from the home. All firearms Jones had listed on an insurance inventory were found in his house.

Both Sherry Lee and her husband are dead. Bruce Lee was fatally shot after killing another man in a burglary before his brother's trial.

The judge also ruled Larry Lee's trial attorney, Alex Zipperer of Savannah, provided an inadequate defense. Zipperer had tried only one other death penalty case, 12 years before Lee's. He was the only attorney representing Lee even though Georgia courts routinely appoint two defense lawyers to capital cases.

The judge said Zipperer failed to prepare for the sentencing phase of Lee's trial. The only witness he called to persuade the jury to spare Lee's life was his sister, Lynn Grizzard. Zipperer asked her a total of seven questions. Grizzard described Lee as "gentle" and "nonviolent," and said she'd never known him to hurt anyone.

Michael Koval, the lead attorney handling Lee's appeal, declined to comment other than to say, "The judge issued a strong and clear order."