"I'm delighted, humbled and honored by the appointment," he told The Associated Press hours after the high court named Birkett on Wednesday. "I always aspired to be on the bench."
Birkett, 55, has previously run for attorney general and lieutenant governor and, despite losing those races, his name has come up frequently as a potentially strong candidate for high office in Illinois.
Birkett said several fellow Republicans approached him in the lead up to the 2010 governor's race and asked if he intended to throw his hat into the ring. He told them he didn't plan to run, saying he had his eye on an appellate court appointment, Birkett told the AP Wednesday.
"I hadn't made it public, but I was very candid with others who wanted to run for governor that this is something I wanted to do," he said. "I passed up the run for governor because this is what I wanted to do."
He told his staff Wednesday that his last day as DuPage County's prosecutor will be Dec. 10; he'll be sworn in as a justice three days later. He replaces Justice Jack O'Malley, who plans to step down next month.
Birkett said he viewed service as a judge as the pinnacle of the legal profession. Given the chance, he said he would like to serve someday on the Illinois Supreme Court or even on the U.S. Supreme Court. The Second District, based in Elgin, hears cases from 13 northern Illinois counties, including DuPage.