DENVER (AP) – A man convicted of killing four people at a Chuck E. Cheese restaurant nearly 19 years ago moved closer to execution following the rejection of his appeal by a federal appeals court.

The 10th U.S. Circuit Court of Appeals Monday rejected Nathan Dunlap’s request to have his death sentence overturned. A three-judge panel rejected Dunlap’s arguments that his attorney erred in not presenting evidence of mental illness during the sentencing phase.

The panel found that the decision by Dunlap’s attorney was meant to prevent other evidence from being presented in court, including that Dunlap bragged about the July 1993 slayings while in custody.

Dunlap is one three men on death row in Colorado, which hasn’t executed anyone in 15 years.

Dunlap could appeal the decision to the U.S. Supreme Court.

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