But Thomas Grasso, 30, decided he would rather die than spend two decades in a New York jail. When an Oklahoma court gave him the death sentence he said he wanted the lethal injection immediately.
The Oklahoma Attorney-General, Susan Loving, seized on Grasso's wish as a way of having a legal showdown with New York over the death penalty, refusing to return him.
New York's prison authorities, however, insisted: Oklahoma had to return Grasso to serve his life term, they said, because his first conviction was in New York.
To back their claim, the New York officials cited an agreement signed by 47 states and the District of Columbia that obliged New York to send Grasso for trial in Oklahoma and, in turn, obliged Oklahoma to send him back to serve his 20-year sentence.
Under the same agreement, New York was obliged after 20 years to return him to Oklahoma where, under state law, he would be executed within 90 days barring appeals.
Grasso's lawyer, Johnnie O'Neal, who has made a career in Oklahoma out of fighting against the death penalty, is nevertheless behind his client because he says it is 'cruel and unusual to tell someone they're going to die and then put it off for a set number of years. Mr Grasso would serve 20 years and then know that 90 days later he would be dead'.
If New York wins the battle, it will cost the state dollars 500,000 (pounds 318,000).
In a similar dispute over a man who had killed people in New York and Florida, the convicted murderer is serving his 25-year sentence in New York.
Grasso was first convicted of strangling an 82-year-old man on Staten Island and then an 87-year-old woman in Oklahoma. He confessed to both crimes.
New York officials maintain: 'There is absolutely no authority whatsoever for Oklahoma to retain physical custody of Mr Grasso.' But on the other hand, the Oklahoma authorities say with equal force that if anyone wants to die 'we're willing to accommodate them'.