Nearly 24 years after the bodies of five people shot execution-style were found along a remote road, the first trial has begun in what became one of the state's oldest unsolved mass murder cases.

Romeo Pinkerton, 49, a convicted robber, faces a possible death sentence in the killings known as the Kentucky Fried Chicken murders.

Pinkerton's cousin, Darnell Hartsfield, 46, who also has an extensive criminal record, is charged in the case as well. His trial is to be held some time next year.

Both men have pleaded not guilty.

Prosecutors say Pinkerton and Hartsfield entered the KFC near closing time on the night of Sept. 23, 1983. Police said they robbed it, then forced the five victims into a van, drove about 15 miles to an oil-field road and fatally shot them.

"The case has been represented by a lot smarter people than I as the most significant unsolved case in the state of Texas," said George Kieny, a former FBI investigator brought into the long-stalled case.

Kieny collected DNA samples from Pinkerton and Hartsfield that ultimately led to the capital murder indictments against the pair in November 2005.

Four of the victims worked at the KFC in Kilgore, about 25 miles east of Tyler and 115 miles east of Dallas. The fifth was a friend of one of the employees.

The victims were Mary Tyler, the restaurant's 37-year-old assistant manager; co-workers Opie Ann Hughes, 39, and Joey Johnson and David Maxwell, both 20; and Monte Landers, 19, a friend of Johnson and Maxwell.

Police were summoned to the restaurant after Tyler's daughter came to pick up her mother but found no one there. Investigators found blood on the floor and a cash register tape showing about $2,000 was missing from the cash box.

Preliminary jury selection in Pinkerton's trial began Monday in New Boston, where state District Judge J. Clay Gossett moved the trial because of publicity about the case in Henderson, about 90 miles away.

Pinkerton, wearing blue jeans and a blue T-shirt over a long-sleeved white undershirt, said little in the nearly empty courtroom Monday.

In response to questions from the judge, he replied five times that he had no objection to the exclusion of five prospective jurors who gave work- or health-related reasons.

Gossett, who sent out 350 jury summonses, has said the trial could take as long as three months. Individual questioning of potential jurors, a tedious task likely to take weeks, was to begin next week.

The case remained open until April 1995, when a Kilgore man convicted of federal drug trafficking charges was indicted for capital murder after a torn fingernail believed to be his was found on one of the victims' bodies. Subsequent DNA tests, however, exonerated him. Charges were dropped and the case remained unsolved.

Then in late 2001, Kieny, taking advantage of newly developed DNA technology, took samples from Hartsfield and Pinkerton that tied the pair to the KFC murders.

Hartsfield has been in a Texas prison since 1995 on a 40-year sentence for delivery of a controlled substance and engaging in organized criminal activity.

In 2003, he told a grand jury he wasn't at the restaurant. But with the new DNA results, plus earlier witness accounts that put him there that night, prosecutors charged him with perjury.

A jury convicted him and he was sentenced to life in prison because of his criminal record, which also includes aggravated robbery, burglary and reckless endangerment.

Two weeks later, Texas Attorney General Greg Abbott announced capital murder indictments against him and Pinkerton, a convicted burglar who'd been paroled at least five times. Prison records show Hartsfield was arrested for aggravated robbery three days after the KFC slayings.

Pinkerton told investigators he was in prison at the time of the slayings but records show he was paroled two days before the murders.

Even if Pinkerton is convicted, his execution ultimately may be in doubt. Defense lawyers say there is evidence in his past of mental retardation, which under a U.S. Supreme Court ruling could prevent him from being put to death. Prosecutors are contesting the mental retardation claims.