Although almost 10 years and at least $6 million were required to get serial killer Ted Bundy executed, the time and money were well spent, Attorney General Bob Butterworth says.

"I personally believe Ted Bundy was the type of person, that if he had escaped or could have been let loose at some point in time, would have killed again," Butterworth said Wednesday.Bundy was executed Jan. 24, ending nearly a decade of appeals of his convictions for murdering two Florida State University students and a 12-year-old Lake City girl.

"Ted Bundy in his last days admitted killing about 36," Butterworth said. "I don't believe society had any other choice but to make sure that he was convicted, that he was incarcerated and that he was executed."

Death penalty opponents say it would have been cheaper to lock him up for life. Although Butterworth disagrees, no one has precise costs.

State prison officials say it now costs almost $36 a day - or about $13,000 a year - to hold each inmate. But they keep no figures for death row, where some 300 murderers require tighter security and usually receive state-paid legal help.

"I'd personally be surprised if it's less than $100,000 a year for a person on death row," Butterworth said.

Some officials estimate overall costs, including investigations in other states, at up to $10 million in the Bundy case. Butterworth spokesman Tom Hillstrom said estimates in the range of $6 million to $7 million "are credible figures."

A Washington law firm donated almost $1 million worth of lawyers' time and $100,000 in expenses representing Bundy on appeal.

"In terms of time and dollars, the Bundy case would have absolutely overwhelmed us," said Larry Spalding, director of the state office that usually handles such appeals.

Hillstrom estimated the attorney general's office spent between $750,000 and $1 million successfully defending the convictions.