(WHAS11) -- A man who killed three of his classmates at a Paducah high school in 1997 will not be able to withdraw his guilty plea.
A federal appeals court ruled Thursday that if 29-year-old Michael Carneal wanted to take back his plea he should have done it years ago.
Carneal was 14 when he shot and killed three teens at Heath High School in 1997 he wounded five others.
Carneal's attorneys argued that he was mentally unfit to accept responsibility for the crime because of his age.
He pleaded guilty in 1998 but did not file for state post-conviction relief until 2004.
The appeals court judge says Carneal was mentally competent in 2004 and if he wanted to change his plea, he should have done it then.