California has executed a triple murderer in the first death sentence to be served in three years, and the first under Governor Arnold Schwarzenegger.
Campaigners called for Beardslee to be given a chance to reform
Donald Beardslee, sentenced to death for two 1981 killings, was given a lethal injection shortly after midnight (0800 GMT) at San Quentin State Prison.
Mr Schwarzenegger rejected a plea for mercy, saying Beardslee had understood the gravity of his crimes.
Beardslee's lawyer, Steven Lubliner, said the execution "demeaned everyone".
His defence team had argued he was suffering from brain disorders when he killed Stacey Benjamin, 19, and Patty Geddling, 23, in a dispute over drugs in San Francisco in 1981.
Beardslee had been on death row since 1984.
He had previously served seven years for the second-degree murder in 1969 of Laura Griffin, a woman he strangled and stabbed after meeting her in a bar in Missouri.
The Supreme Court rejected without comment two appeals against his death sentence:
Beardslee shot and stabbed his victims
- that the lethal injection he was due to receive was a cruel and unusual punishment
- that jurors were unfairly influenced when they returned the death verdict.
Governor Schwarzenegger upheld the sentence, describing Beardslee as "not... a man who is so generally affected by his impairment that he cannot tell the difference between right and wrong".
Since his election just over a year ago, the governor has denied clemency to one other person on death row, Kevin Cooper, who was convicted of mass murder but says he is innocent. A federal appeals court subsequently granted Cooper a stay of execution.
California, where some 600 people are currently on death row, had not carried out an execution since January 2002.
A crowd of about 200 people protested against the execution outside San Quentin. Inside, Beardslee spent his final hours in a waiting room where he was able to watch television, read and talk to his spiritual adviser.