A man sentenced for fatally beating a co-worker seven years ago was executed by lethal injection in Virginia on Thursday night, becoming the fourth convict in the state to be put to death this year.

Christopher Emmett, aged 36, was pronounced dead at 9:07 p.m. at the Greensville Correctional Center in Jarratt, as reported by Larry Traylor, a Department of Corrections spokesman. He was convicted of thrashing a colleague to death with a brass lamp in 2001 in order to steal the man’s money to purchase crack cocaine.

The U.S. Court of Appeals for the 4th Circuit, invoking an April  U.S. Supreme Court ruling that the three-drug protocol utilized in capital punishments in Kentucky and most other states does not represent a cruel and unusual sentence, rejected Emmett’s argument claiming that Virginia’s execution system is unconstitutional. Emmett’s attorneys asserted that prisoners might not be completely anesthetized before receiving the drugs that can produce unbearable pain.

Virginia Gov. Timothy M. Kaine, who drew the public’s attention upon the fact that Emmett’s challenge to the state’s lethal injection method was rejected by the courts, refused to intervene. “I find no compelling reason to set aside the sentence that was recommended by the jury, and then imposed and affirmed by the courts,” Kaine said in a statement, according to the Washington Post.

In a lethal injection procedure similar to the method used in most states, Virginia initially administers sodium thiopental, which causes unconsciousness, followed by a drug that paralyzes the muscles and another that provokes cardiac arrest. The final two drugs can generate excruciating pain if the first drug is not administered correctly.

Virginia has put to death 102 people since the Supreme Court restored the death sentence in 1976.