The families of two black teenagers abducted and killed in 1964 are suing Franklin County, claiming the sheriff there didn’t properly investigate the deaths.

The families are seeking damages for the county’s role for “flagrant violations” of the teenagers’ constitutional rights, including their wrongful deaths, according to the lawsuit. The lawsuit, filed in federal court in August, alleges that then-Sheriff Wayne Hutto didn’t do enough to find out how the boys died. Hutto died in 1984.

Franklin County says the lawsuit should be dismissed because the three-year statute of limitations expired in 1967.

“After 40 years and the passing of most individuals with knowledge of the occurrences in issue, the statute of limitations must be upheld,” the county says in court papers.

On May 2, 1964, Klansmen reportedly abducted Henry Hezekiah Dee and Charles Eddie Moore before beating and killing them. On July 12, 1964, authorities fished Dee’s and Moore’s bodies from the Mississippi River.

In 2007, a federal grand jury named Hutto as a coconspirator in the Klan scheme when they indicted reputed Klansman James Ford Seale, now serving three life sentences in a prison in Terre Haute, Ind., for kidnapping and conspiracy in the case.

In May, the full 5th U.S. Circuit Court of Appeals will hear arguments on whether Seale’s conviction on kidnapping and conspiracy charges should be tossed out, as a three-judge panel of the court earlier ruled.

Michael Wolf of Jackson, who is representing Franklin County, says in court documents that “there is no genuine evidence which exists linking the sheriff of Franklin County to the events alleged.”

Franklin County says in court documents that Hutto made an honest investigation.

According to court documents, the families of Dee and Moore say they knew nothing of Hutto’s role until the 2007 indictment.

The lawsuit alleges that Moore’s mother went to Hutto about her missing son, only to be told he had gone to visit relatives in Louisiana when Hutto knew that wasn’t so.

When Moore’s mother she did travel there, she was told her son hadn’t been seen, according to the lawsuit.

The lawsuit also alleges Hutto and a deputy also misled the FBI investigators in the case by saying they knew nothing about the disapperances.

The lawsuit claims Hutto never started an investigation into the disappearances even though he had promised family members he would.