In February, Duncan's defense team went to Riverside County prosecutors, offering to have their client plead guilty in exchange for a sentence of life in prison, said John Hall, a spokesman for the Riverside County district attorney's office.
It was a deal the Riverside District Attorney said he accepted only because Duncan has already been sentenced to die for killing another little boy in another state.
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"Mr. Duncan has earned the right to be executed, " states Paul Zellerbach, Riverside County District Attorney.
"It was fourteen years, just within two weeks of being exactly fourteen years that we waited to get the point we're at now. It' was the longest road that I've ever been on," according to Diana Gonzalez, Anthony's mother.
Her long ordeal is nearing an end.
In addition to accepting life in prison without parole, Duncan will wave all rights to appeal.
Zellerback says agreeing to the deal was one of the most difficult decisions in his career. One he made, after consulting Anthony's family, and because Duncan has already been sentenced to death for murders in Idaho.
In 2008, a federal jury convicted Duncan of murdering 9-year-old Dylan Groene, his mother, Brenda Groene, her fiancé, and another of her sons in Idaho. Duncan was sentenced to death and also given nine life terms for those crimes.
"We're ready for a conclusion," according to Diana Gonzalez, Anthony's mother. "We're ready for it to be done. It won't ever be closed, but it will be over, and we can now mourn Tony's death the way we should have in the beginning."