ST. LOUIS (AP) — Missouri is preparing for its second execution of 2017, even as condemned inmate Marcellus Williams continues to declare his innocence.

Williams is scheduled to die by lethal injection at 6 p.m. Tuesday at the state prison in Bonne Terre for the 1998 stabbing death of Lisha Gayle. The onetime St. Louis Post-Dispatch reporter surprised the burglar and was killed at her University City home.

Attorneys for Williams contend that testing conducted in December using techniques that were not available at the time of the killing showed DNA found on the knife matches an unknown man, but not Williams. They say previous DNA testing of hairs from Gayle’s shirt and fingernails also excluded Williams, and that footprints at the scene did not match Williams.