A former Ku Klux Klansman will go on trial tomorrow for the murder of two young black men who were abducted, beaten, and dumped into the Mississippi river in 1964.

James Ford Seale, 71, a former crop duster and sheriff’s deputy, faces spending the rest of his life in prison if convicted in a trial that civil-rights groups hope will be the first prosecution in a wave of rekindled investigations into unsolved race killings from the era.

Mr. Seale and fellow Klansmen are alleged to have picked up the two 19-year-olds — Henry Dee and Charles Moore — as they were hitchhiking in rural southwestern Mississippi.

The Klansmen, who believed the pair were trying to smuggle guns into the state, drove them into the woods where they were questioned and beaten with tree branches.

They were then bound with duct tape and taken by boat on to the river where — still alive — they were thrown overboard, weighted down with chains and an engine block. The bodies were not discovered for two months.

Mr. Seale, 71, denies kidnapping and conspiracy charges. He was questioned after the killings but, despite allegations that he cheerfully discussed the murders in private, the case was dropped.

He then disappeared until 2005, when Mr. Moore’s older brother, Thomas, and a Canadian television journalist discovered him living in Mississippi despite his family’s assertion that he had died years previously.

The case harks back to the American South’s unhappy civil rights era — a time of legalized racial segregation, burning crosses, and Klan-inspired lynchings and bomb attacks on black churches.

It is the first case involving an alleged former Klansman since Attorney General Gonzales announced in February that investigators were to re-examine almost 100 suspected racist killings in the southern states during the 1950s and 1960s. While civil-rights groups expect a flood of similar cases, skeptics fear the crimes, and potential witnesses, are now just too old.

“Every day that goes by, these cases get more and more difficult,” said Doug Jones, a former U.S. attorney who successfully prosecuted Bobby Cherry, a former Klansman, for bombing a church in 1963.

The trial in 2002 would have fallen apart if it had been heard just months later as some of the main prosecution witnesses had died, he said.

David Garrow, a Cambridge University academic and a Pulitzer-winning biographer of Martin Luther King, has expressed other concerns about such cases.

He said, “My fear is that we sign off on watering down our criminal justice standards because of who the defendants are and what they’re accused of.”

More than 300 people have been called for jury selection for Mr. Seale’s trial in Jackson, Miss.

Each was required to complete an extensive questionnaire about their attitudes to race.

The trial will hear evidence that Mr. Seale’s now-dead brother implicated him in the crime. Charles Edwards, an alleged accomplice on the day of the murders, is also expected to testify against him.

Thelma Collins, the sister of Henry Dee, said she gave up hoping long ago that his killers might be brought to justice.

She said, “I thought about Henry and what happened every day, and I still cry, but it’s something I never talked about with my children.

“Justice should be served because Henry never got to have a family and enjoy grandchildren like he should have.”