PHILADELPHIA, Miss. (AP) _ The state's decision to consider reopening the investigation into the 1964 slayings of three civil rights workers has raised hopes a cloud of collective guilt may be lifted from this small community.

What Philadelphia's 8,000 residents need now, says the editor of a newspaper here, is a cathartic event such as a new trial to help them deal with the emotional fallout from the town's complicity in the attempted coverup of the June 21, 1964, slayings of James Chaney, Andrew Goodman and Michael Schwerner.

''The people here didn't step forward and speak out against the murders 25 years ago. That's why we need to do it now,'' said Stanley Dearman, editor and publisher of the Neshoba County Democrat.

Last week, Attorney General Mike Moore said he was considering reopening the investigation into the killings, which were dramatized in the movie ''Mississippi Burning.'' Moore said he would examine the files before making a final decision.

Nine Mississippians, including a deputy sheriff, eventually went to prison on federal charges for violating the victims' civil rights.

However, the state never prosecuted the case, in which Chaney, Goodman and Schwerner were arrested in Neshoba County on a traffic charge and then turned over to a Ku Klux Klan lynch mob that shot them and buried the bodies in an dam near Philadelphia.

On Wednesday, during a memorial observance, Mississippi Secretary of State Dick Molpus issued a public apology to the victims' families.

''We deeply regret what happened here 25 years ago,'' he said. ''Every decent person in Philadelphia and Neshoba County and Mississippi feels that way.''

Wednesday's ceremony, also attended by Gov. Ray Mabus, marked the first time state officials had honored the victims. Schwerner and Goodman, white civil rights volunteers from New York, and Chaney - a black civil rights worker from nearby Meridian - were killed while working on a voter registration drive.

Dearman, editor of the weekly paper since 1966, said the observance and movie had helped weaken some of the barriers holding back the emotions of residents, including his own feelings.

''There's a lot of denial in Philadelphia, people saying they weren't involved or responsible for what happened,'' he said. ''I used to feel that same way but I've come to believe in the concept of collective guilt. And I've come to the conclusion that everybody in a community has a responsiblity to stand up when they see something wrong happen.''

He added that an investigation and trial could provide the final step in the community's acceptance of its responsibility.

''A trial undoubtedly would dredge up a lot of pain and turmoil,'' he said. ''But while there have been many positive changes here, I don't think we're ever going to be able to completely put the past behind us until we've dealt with the murders.''

Molpus, a Philadelphia native, said he, too, would support reopening the investigation if Moore decides to go ahead.

''The attorney general took an oath to uphold the law, as I did,'' said Molpus, whose mother still lives in Philadelphia. ''But I admit to having mixed emotions, it could tear up the community and turn us back toward a dark and diverse time in our history.''

Charles McClain, mayor of Philadelphia, said he feared reopening the case would divide the community.

However, Ben Chaney, whose brother was slain, says he thinks it should be reopened.

''It would help bring attention to some of the things that never were dealt with 25 years ago, such as the Klan beatings at the Mount Zion Methodist Church near Philadelphia,'' he said.

J.R. ''Bud'' Cole was severely beaten by hooded and robed Klansmen following a meeting at the church, which was burned the week before Chaney, Goodman and Schwerner were killed.

There also was no investigation into the burning of the church, which was later rebuilt and was part of last week's memorial observance.

''That's the way things were back then,'' Cole said. ''A white man could do anything to a Negro and never be held accountable.''

But Dearman says much has changed in Philadelphia, which now has an integrated police force and fire department.

And a recent KKK rally in Philadelphia drew little support, he said.

''Only about a hundred people showed up, and most of them were there as observers,'' Dearman said. ''In fact, something happened I've never seen before - white people were actually shouting at the Klan to go away and leave us alone.''

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EDITOR'S NOTE - Strat Douthat is The Associated Press' Southeastern regional writer, based in Atlanta.