HOUSTON (AP) — A federal appeals court is allowing attorneys for a 44-year-old convicted killer to move forward with an appeal that questions whether he's eligible for the death penalty for the 2004 suffocation of retired college professor abducted in Fort Worth.

The 5th U.S. Circuit Court of Appeals has ruled Edward Lee Busby may pursue arguments that he's mentally impaired, making him ineligible for execution, and that he's had deficient legal help at his trial and in earlier stages of his appeals.

Busby was convicted of the slaying of 77-year-old retired Texas Christian University professor Laura Lee Crane, who was abducted from a Fort Worth grocery store parking lot. He was arrested in Oklahoma City driving Crane's car and led authorities to her body in Oklahoma just north of the Texas border.