PHILADELPHIA, Miss. – Forty-one years to the day after three civil rights workers were beaten and shot to death, an 80-year-old former Ku Klux Klansman was found guilty of manslaughter yesterday in a trial that marked Mississippi’s latest attempt to atone for its bloodstained, racist past.

The jury of nine whites and three blacks took less than six hours to clear Edgar Ray Killen of murder but convict him of the lesser charges in the 1964 killings that galvanized the struggle for equality and helped bring about the passage of the 1964 Civil Rights Act.

Killen, a bald figure with owlish bifocals, sat impassively in his wheelchair, an oxygen tube up his nose, as he listened to the verdict.

“Forty-one years after the tragic murders … justice finally arrives in Philadelphia, Miss.,” said Rep. Bennie Thompson, a Democrat, and Mississippi’s only black congressman. “Yet, the state of Mississippi must see to it that the wrongs of yesterday do not become the albatrosses of today.”

The murder charge carried up to life in prison. But Killen could still spend the rest of his life behind bars; each of the three manslaughter charges is punishable by up to 20 years. Judge Marcus Gordon scheduled sentencing for tomorrow.

Civil rights volunteers Andrew Goodman and Michael Schwerner – two white New Yorkers – and James Chaney, a black Mississippian, were intercepted by Klansmen in their station wagon on June 21,1964. Their bodies were found 44 days later buried in an earthen dam, in a case that was dramatized in the 1988 movie “Mississippi Burning.”

Prosecutors said Killen – a part-time preacher and sawmill operator – organized the carloads of Klansmen who hunted down and killed the three young men.

Yesterday, cheers could be heard outside the two-story, red brick courthouse in this small town after Killen was convicted. Passersby patted Chaney’s brother, Ben, on the back, and a woman slowed her vehicle and yelled, “Hey, Mr. Chaney, all right!”

Ben Chaney thanked prosecutors and “the white people who walked up to me and said things are changing. I think there’s hope.”

Schwerner’s widow, Rita Schwerner Bender, hugged the district attorney, Mark Duncan, and called it “a day of great importance to all of us.” But she said others also should be held responsible for the slayings.

“Preacher Killen didn’t act in a vacuum,” she said. “The state of Mississippi was complicit in these crimes and all the crimes that occurred, and that has to be opened up.”

Killen’s wife, Betty Jo, went to her husband with tears in her eyes and hugged him. Killen, who was in a wheelchair because of a logging accident in which he broke his legs, was surrounded by more than a dozen armed officers as he was wheeled from the courthouse and taken off to jail. He slapped two television microphones and a TV camera on the way out.

Juror Warren Paprocki said the jury initially was split.

“On the one hand, this guy needs to be convicted. And on the other hand, the state needed to present better evidence,” said Mr. Paprocki, 54, of Philadelphia.

Prosecutors had asked the jury to send a message to the rest of the world that times have changed in Mississippi and that the state is committed to bringing to justice those who committed violence to preserve segregation in the 1950s and ’60s.

Killen’s lawyers conceded he was in the KKK but said that did not make him guilty. They pointed out that prosecutors offered no witnesses or evidence that put Killen at the scene of the crime. Killen did not take the stand, but has long claimed he was at a wake at a funeral home when the victims were killed.

The defense attorney, James McIntyre, said he will appeal on the grounds that the jury should not have been allowed to consider the manslaughter charges.

With a murder charge, prosecutors had to prove intent to kill. With a manslaughter charge, they had to prove only that a victim died while another crime was being committed.

“It’s not the perfect ending in this case. I believe we proved murder and I believe he was guilty of murder,” the district attorney said. But he added: “The bottom line is they have held Edgar Ray Killen accountable for his actions.”

Goodman’s 89-year-old mother, Carolyn, said from her home in New York yesterday that the real heroes were those who stood up to the hate groups.

“I know a lot of people in Mississippi who have risked their lives,” Carolyn Goodman said. “I would say those are the most important people in my life. All the people who have stood up and the victims of the Klan.

“I think most of the people are wonderful down there,” said Ms. Goodman, who was in Philadelphia last week to testify about her son. “There are a few rotten apples in every barrel.”

Killen was only person ever brought up on murder charges in the case by the state of Mississippi.

Killen was tried in 1967 on federal charges of violating the victims’ civil rights. But the all-white jury deadlocked, with one juror saying she could not convict a preacher. Seven others were convicted, but none served more than six years.

At the time of their deaths, Chaney, Schwerner, and Goodman were in Neshoba County to look into the torching of a black church and help register black voters during what was called Freedom Summer. The three were stopped for speeding, jailed briefly, and then released, after which they were followed out of town by a gang of Klansmen and killed.