Charles Peterson was scheduled to testify for the prosecution next month in the capital murder trial of a man charged with killing a Pennsylvania state trooper in 2005.

Instead, the 26-year-old was gunned down in front of his home in St. Clair Village on Jan. 3 and died shortly after.

Now, Mr. Peterson is No. 4 on a list of 126 alleged "snitches" that has been distributed in various neighborhoods throughout the city in recent weeks. Guards confiscated copies of the list from inmates at the Allegheny County Jail, where officials believe the list originated. Some copies also made it out of the jail with inmates headed for state prisons.

Why would a dead man be put on a fresh list of people said to be cooperating with authorities?

Detective Steve Hitchings of the city homicide squad said, "I think it was a list that kept getting passed around and some of those names were very old. People just kept adding names to it."

Mr. Peterson had been subpoenaed to testify in the murder trial of Leslie D. Mollett, who is charged with killing Cpl. Joseph R. Pokorny Jr. with the trooper's own service weapon after a car chase that ended in Carnegie.

Mr. Peterson was one of several witnesses who were in a room at an Extended Stay America hotel near the shooting.

At the time of Mr. Peterson's slaying, his aunt, Betty Porterfield, 55, of East Liberty, said he'd seen nothing vital the night of the homicide and she did not think the shooting was related to the murder case. "He was not a major witness. He didn't have anything to offer," she said.

Three others named on the snitch list also died violent deaths and may have been targeted for cooperating with authorities, police said.

Among them is Edward Howard, known as "Gusto." who had a record for drug crimes and cruised the North Side streets in a wheelchair after he was paralyzed in a shooting.

The 24-year-old was fatally shot on Nov. 4, 2003.

Reginald Huff, who was acquitted in Mr. Howard's killing, said the victim's other nickname was "The Rat," because he'd informed on a legion of drug dealers and street toughs.

Mr. Huff said at the time of his acquittal that a hundred people could have killed Howard.