LOUISVILLE, Ky. (WDRB) -- The man who pleaded guilty to murdering his stepson and received a life sentence in the case has now filed a motion to appeal.

The Commonwealth Attorney's Office says Josh Gouker filed a motion claiming "ineffective assistance of counsel."

The motion is the only option available to defendants who plead guilty.

"This is not unexpected from a defendant like Josh Gouker," said assistant Commonwealth's attorney Leland Hulbert.

Last year, Gouker claimed sole responsibility for killing 14-year-old Trey Zwicker in 2011.

He was sentenced to life in prison without the possibility of parole for 20 years.

His son, Josh Young was also charged in Trey's murder, but was acquitted by a jury in August 2013.

Young is speaking with talk show host Dr. Phil this week.

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