Tommy Zeigler turns 70 this month. He has lived more than half his life on Florida's death row.He has always said he did not kill his wife, her parents and another man at his Winter Garden furniture store on Dec. 24, 1975. But time and again, one appeal after another, the courts have not believed him.Now may be his best chance to prove his innocence. It may also be his last.Attorneys filed a motion this week seeking court approval to use a special DNA test to examine evidence presented at the trial. The technology allows experts to analyze skin cells that can be left on one person when they are touched by another. It has been used to free other inmates across the country.In more than 800 pages of documents and exhibits, Zeigler's lawyers retrace a story that has long raised questions in Orange County — namely, why a respected businessman with no criminal history would kill his family on Christmas Eve."The evidence based on which he was convicted is extremely thin, and with every passing year becomes less and less reliable because of new discoveries that are made," said his New York attorney Dennis Tracey, who has worked on the case for free since 1986.The new motion offers fresh revelations.A key witness changed his story.Someone attempted to rob a business right across from the furniture store that very night.And, most important: There is a new suspect with a financial motive for the crime.Prosecutors in Orange County have remained adamant that Zeigler is guilty. A spokesperson for State Attorney Jeff Ashton said they had yet to look through the new filing. In past interviews though, when asked if Zeigler might get a new trial, Ashton responded: "Not in a million years."But the new DNA testing, if granted, could finally determine once and for all whether Zeigler is a calculating killer or a wronged man who spent almost 39 years on death row for a crime he did not commit.• • •Zeigler grew up in Winter Garden, a town of 6,000 just northwest of Orlando. He ran the W.T. Zeigler Furniture Store his parents opened in 1939 and also owned rental properties. He was friends with the town police chief and other local dignitaries. A youth football coach, he met and fell in love with an elementary school teacher named Eunice. They married at the First Baptist Church on July 25, 1967, his 21st birthday.The couple lived next door to his parents. They raised Persian show cats. They were trying to have a baby. Eunice documented their intimate moments on charts that ended two weeks before Christmas 1975.On Christmas Eve, the Zeiglers were supposed to drive to a municipal judge's Christmas party with Eunice's parents and their friends, town police Chief Don Ficke and his wife. They never made it.Just after 9 that evening, Zeigler called the chief at the party and said: "Don, I've been shot."When officers arrived at the furniture store, Zeigler opened the door and collapsed with a bullet wound in his stomach. Inside was a scene that shocked police and members of this small citrus farming community.Eunice, 32, had been shot in the back of the head. Eunice's father, Perry Edwards, 72, had been shot multiple times and beaten with a linoleum crank. Her mother's body lay behind a sofa. A local citrus foreman, Charles Mays, 35, was also shot and bludgeoned.• • •At the hospital, recovering from his gunshot wound, Zeigler told police his version of what happened.He went to the store to make some deliveries. His in-laws and Eunice were to stop by to pick out a recliner for Christmas.Several people attacked him and knocked off his glasses. Zeigler kept a gun and fired at the blurry figures.Two witnesses helped make the case against Zeigler. The first, Zeigler's handyman, came to police with one of the murder weapons. Edward Williams said he'd gone to the store to help Zeigler make some deliveries Christmas Eve. Zeigler had pointed a gun at him and pulled the trigger. The weapon misfired, Williams said, and Zeigler handed Williams the gun. The other, fruit picker Felton Thomas, said that he'd gone to Zeigler's store that same evening with his friend, Charles Mays. Zeigler took the two black men to an orange grove to shoot weapons. Later, they returned to the furniture store and Zeigler invited them inside. Thomas grew suspicious and left. Mays went inside. Neither man saw Zeigler kill his family, but police would speculate that they had been lured to the store by Zeigler so he could frame them for the murders. With two witnesses, the Orange County Sheriff's Department turned to forensic evidence.Detective Donald Frye was fresh off blood splatter training when he arrived at the scene. He looked at the patterns and surmised that the victims were killed at different times. Frye believed that Zeigler killed his wife and in-laws first, then lured Mays and Thomas to the furniture store. The trip to the orange grove with Mays and Thomas, the detective speculated, was a way for Zeigler to get their fingerprints on the gun. The gunshot wound to Zeigler's stomach was a way to make it look like he fought back.As for a motive: $520,000 in insurance taken out on Eunice's life just a few months earlier.Five days after the killing, Frye arrested Zeigler in his hospital bed.Six months later, a jury convicted him and recommended life in prison. A judge sentenced Zeigler to death. • • •Of all the evidence collected in the nearly four decades since his conviction, it is Zeigler's rust-colored, long-sleeved shirt and his wife's gray tweed jacket that could once and for all solve a mystery.Attorneys want to know if Zeigler had any of his father-in-law's DNA on the shirt. If there is none, there's no way Zeigler killed Edwards. They also want to know who touched Eunice's jacket after she was shot. The lining inside the jacket and a sock had blood on them, indicating someone took the time to button up the jacket and replace a shoe. It could have been the killer.A new type of DNA analysis may be the way to answer those questions.This type of examination, which amplifies and analyzes skin cells left behind, only became available in the United States a few years ago.The tests were used to exonerate a former state trooper accused of killing his wife and two young children in Indiana. They helped free a Colorado man who was accused at age 15 of stabbing a woman in a field near his home. Both men spent decades in prison."With modern testing techniques, this touch DNA often can be detected, revealing the identity of the person who deposited the blood on the clothing in addition to the identity of the source of the blood," said forensic scientist Richard Eikelenboom, who specializes in touch DNA and formerly worked in the crime-solving laboratory of the Netherlands Forensic Institute.At Zeigler's 1976 trial, former State Attorney Robert Eagan demonstrated for the jury how he believed Zeigler grabbed his father-in-law in a headlock and bashed him in the head with the a heavy metal handle used to role out linoleum, depositing his Type A blood on the underarm of Zeigler's shirt.A 2001 DNA test showed that blood stains in the underarm of Zeigler's shirt actually belonged to Mays — not his father-in-law as prosecutors argued during the trial. Zeigler's attorneys say this backs their client's version of events.The 2001 tests were not enough to set aside Zeigler's conviction. Prosecutors argued the sample was too small and may have deteriorated and that it was possible that Edwards' blood had landed on other spots on Zeigler's shirt.Zeigler's attorneys asked to test the whole shirt so they could prove his father-in-law's blood was not on the shirt. That request was denied."Further testing on my shirts will show demonstrably that there is no blood of Perry Edwards on my clothes," Zeigler wrote in an affidavit to the court that is part of the motion, "as there would be if I had beaten and killed Perry Edwards."• • •If the latest DNA tests don't help Zeigler get a new hearing, the findings of private investigator Lynn-Marie Carty might.Carty, 58, a former Mrs. Florida contestant who specializes in reuniting long-lost families, has spent the past four years trying to prove Zeigler did not kill his family. She has drawn former Pinellas County Sheriff Everett Rice, a neighbor, into studying the evidence and now Rice, too, believes Zeigler is innocent. She has traveled all over the state and to Georgia interviewing witnesses and digging through court records.In September 2013, Carty finally got Thomas, the fruit picker and one of the two key witnesses against Zeigler, to meet her. At his request, they sat in the lobby of the Fort Pierce Police Department because he said he was afraid. The interview, which lasted one hour and 41 minutes, was recorded. Thomas said he had never met Zeigler before the day of the murders. He said Mays told him they were going to "Zeigler's" that day. Once there, they met a white man who asked them to go shoot guns in an orange grove. But he's not sure who that man was.After the murders, he said police told him Zeigler had murdered Mays and the others. They did not ask him to identify Zeigler as the white man he'd met. They did not produce a police lineup with Zeigler's picture in it."I still don't know who it was," he told Carty.Zeigler's attorneys and Carty now theorize that the real killer may have been Perry Edwards Jr., Eunice's brother. He bore a resemblance to Zeigler at the time, Carty said. According to a divorce complaint his wife once filed, he beat her and other family members and threatened to kill her. There is no proof that Edwards Jr. was involved in the murders, but Carty said she talked to relatives of his who said he traveled to Florida on Christmas Eve in 1975.He may also have had motive, Zeigler's lawyer argues in the new filing.Edwards Jr. inherited "substantial assets," including property in Levy County, from his parents, the motion states.Edwards Jr. died in 2013. His wife could not be reached for comment.Zeigler's lawyers say it is clear police were not willing to consider other subjects once they zeroed in on Zeigler."If you really compare Tommy Zeigler and Perry Edwards Jr. in terms of their motivation to kill the victims, Perry Edwards had much more motivation," said Tracey, Zeigler's attorney. "He stood to gain millions from the estate of his parents, whereas Tommy Zeigler had a small life insurance policy, he had connections to Winter Garden, he was a model citizen. … It makes no sense."Times researcher Caryn Baird contributed to this report.