Mark Duane Edwards Jr., 24, is scheduled to be killed by lethal injection Sept. 19 at the State Correctional Institution Rockview, Centre County, according to the warrant that was signed Wednesday. It was the 70th death warrant the governor has signed since he took office and the 10th in 2007, but none has resulted in an execution.

"Once the courts find the defendant guilty and sentence him to death, there's a warrant issued and the governor has no option but to sign it," said Chuck Ardo, spokesman for Mr. Rendell.

The governor has the discretion to review an appeal, but not a warrant, he said.

James Moreno at the habeas unit of the Defender Association of Philadelphia, the attorney of record for Mr. Edwards, could not be reached for comment.

At the defendant's 2004 trial, public defender Dianne Zerega argued that Mr. Edwards was borderline retarded and on drugs at the time of the killings.

A Fayette County jury found him guilty of breaking into a mobile home and gunning down Larry A. Bobish Sr., 50, Joanna Marian Bobish, 42, and Krystal Leigh Bobish, 17, on April 14, 2002. The jury returned three first-degree murder convictions and one second-degree murder conviction for death of Krystal Bobish's unborn child, which was at 28 weeks' gestation.

The jury also found the defendant guilty of arson and attempting to kill Mr. Bobish's 12-year-old son, Larry Bobish Jr., a key witness to the shootings. The boy survived gunshot wounds to the hand and head and a stab wound to the neck. He testified that he played dead and only fled when he realized the house was on fire.

Witnesses said that Mr. Edwards shot the Bobish family to avoid a drug debt. Two days before the killings, Mr. Edwards and a friend reportedly stole six bottles of a street drug called "wet" -- cigarettes dipped in formaldehyde mixed with PCP -- from Larry Bobish Sr. at gunpoint.

Mr. Bobish paged the defendant repeatedly, seeking payment for the drugs, and threatened to call police. Two witnesses testified they heard the defendant say he planned to kill the Bobishes.

During a police interview, Mr. Edwards waived his Miranda rights. He stated that he killed the parents but did not recall shooting the son and daughter.

Last year, the state Supreme Court affirmed the convictions on appeal. In April, the U.S. Supreme Court declined to hear Mr. Edwards' appeal.

Although Pennsylvania currently houses 226 death row inmates, the commonwealth has executed only three people since capital punishment was reinstated in 1978, all during Gov. Tom Ridge's administration.

Texas, which has the highest execution rate, has sent nearly 400 inmates to the death chamber in the same time frame.