As soon as he saw the chipmunk, he knew Michael Skakel was the killer.
Kenneth Littleton, a 23-year-old teacher who had been hired to tutor Michael and his six siblings at their sprawling Connecticut mansion, saw the dead chipmunk on the grounds of Belle Haven Country Club. The small furry animal had been “mashed” with a golf club and then “crucified” — nailed to a patch of grass with golf tees.
Littleton immediately confronted Michael, who at 15 was already a budding alcoholic with a mean streak and a dangerous sense of entitlement.
“Did you do this, Michael?”
“Who else could have done it, Kenny?” was Michael’s eerie reply.
The incident stuck with Littleton because it took place just weeks after the vicious murder of Martha Moxley, the Skakel clan’s 15-year-old next-door neighbor.
“I knew he had committed the murder, in my heart,” said Littleton.
A day before Halloween in 1975, Moxley was bludgeoned to death with a golf club. The blows were so vicious that the club — a six iron that belonged to the Skakels — was shattered to pieces.
“He was a dangerous package,” said Littleton, now 65, of his former charge in Investigation Discovery’s “Guilty Rich,” which will air the former tutor’s first lengthy interview about the notorious case on Oct. 5.
Michael Skakel was eventually convicted of Moxley’s brutal murder, but only in 2002, nearly 30 years after her death. In the meantime, Littleton was fingered twice as a suspect, enduring unfounded accusations and dirty-tricks policing that he says made his life a living hell.
Littleton, a science teacher from a working-class background, was ill-equipped to take on a powerful East Coast family related to the Kennedys, and blames that trauma for his descent into alcohol and mental illness.
Littleton, who now lives in a New England town he would not disclose to The Post, says he was a scapegoat for small-town…