PORTLAND – As the firings of federal prosecutors raise questions in Washington, Maine’s U.S. Attorney Paula Silsby holds her post under an unusual appointment, even though federal documents say her office is vacant.

Last week, the Justice Department released numerous e-mails and other documents as a result of a congressional investigation into the forced resignations of eight other U.S. attorneys.

The documents also say that Silsby, who has held her post for more than five years, is one of a few U.S. attorneys who were appointed by a judge through a process intended for temporary replacements. Silsby is by far the longest-serving prosecutor in that group.

Unlike almost all of her 92 colleagues, Silsby was never nominated by the president or confirmed by the U.S. Senate. In January, Attorney General Alberto Gonzales told the Senate Judiciary Committee that the Bush administration was committed to having a presidentially appointed, Senate-confirmed United States attorney in every district.

Silsby, who was appointed in the early days of the Bush administration in 2001 and previously had been a prosecutor in the U.S. attorney’s office for 24 years, said she doesn’t know why her name was never submitted to the Senate for confirmation review.

“I can’t speak for what happens in Washington,” Silsby, 56, told the Maine Sunday Telegram.

“I’m just focused on doing the work as the office of the United States attorney, addressing the significant issues we have been confronted with,” added Silsby, dismissing the lack of a nomination and confirmation as an “irrelevancy” after more than five years on the job.

U.S. attorneys decide whether to press charges against people accused of federal crimes such as drug trafficking, illegal gun possession and Internet fraud. They also coordinate local efforts to combat terrorism and oversee local offices of federal law enforcement agencies.

U.S. Sen. Olympia Snowe, R-Maine, recommended Silsby for nomination as U.S. attorney by President Bush, but Silsby was never nominated.

Instead, she was appointed on a temporary basis by then-Attorney General John Ashcroft and eventually was appointed by the U.S District Court. She took her oath of office on Sept. 3, 2001.