Kennedy cousin Michael Skakel is suing the town of Greenwich and a former Greenwich police officer.

Skakel says he wants his audio tapes back that he says were used against him at his murder trial.

The seven tapes Skakel says he wants back were recorded when he was writing a book with ghost writer Richard Hoffman called "DEAD MAN TALKING: A Kennedy Cousin Comes Clean."

His attorney says the tapes were illegally seized and that he has asked to get them back several times.

"My client thinks it’s simply unimaginable that such key evidence would go missing," said Skakel's attorney Stephan Seeger.

Seeger says part of what was on those tapes is what Skakel was doing and where he was on the night Martha Moxley was killed in Greenwich back in 1975.

"The tapes were used in his murder trial. They were also used in the grand jury and some of the segments of the tapes were used in the multimedia display that were used in the closing argument in this Skakel murder trial. And they were taken out of context," said Seeger.

Skakel is now suing the town of Greenwich and police investigator Frank Garr, who got the tapes in 1999.

"We just received the complaint and we are in the initial stages of reviewing it," Greenwich Town Attorney Barbara Schellenberg said in a statement to News 12 Connecticut.

Skakel was convicted of murder in 2002 for the death of Moxley, who was bludgeoned with a golf club.

"For a crime not only that he's not guilty of, not only a case that was dismissed, but a crime he was never involved in. He was miles away when this occurred," said Seeger.

Skakel, who is now 60 years old, spent over 11 years in prison but was freed on an appeal in 2013, claiming he did not receive a fair trial due to deficient legal counsel.

Seeger says he doesn't want the tapes to get into the hands of a third party.

"I hope one day we will find out who killed Martha Moxley," said Seeger.

Frank Garr could not be reached for comment.