Bill Allen walked out of federal custody today.

But secrets about a portion of his past are still locked up at the federal Department of Justice in Washington, D.C.

The key figure in the public corruption probe known as Operation Polar Pen has ended his incarceration for bribing state legislators in 2006.

But as Allen gains his freedom, questions remain about how he managed to avoid prosecution for numerous allegations of soliciting teenage and underage prostitutes.

Did the federal government sell out victims of sexual abuse in order to nail some politicians for taking cheap bribes?

“It certainly has that outward appearance,” said Anchorage Police Department spokesman Lt. Dave Parker. “However, I don't know why those decisions were made as they were made. And it would certainly, I think, please the people of the state of Alaska to find those things out."

The probe netted several convictions, but three were overturned, some politicians long under suspicion were never charged, and federal prosecutors themselves came in for widespread condemnation, with one of them committing suicide.

Meanwhile, Allen, the key prosecution witness, seems to have evaded charges for sex crimes.

At issue:

A federal Justice Department decision in 2004 to call off an Anchorage police investigation, and another decision a year ago to prevent the state Department of Law from pursuing a charge against Allen under a federal statute.

"And I certainly feel here at APD some of those who were involved have a sense of almost betrayal -- that what we tried to do, in terms of doing the right thing by our victims, was somehow truncated or somehow not followed through by the federal authorities," Parker said.

Assistant State Attorney General John Skidmore says that when the APD probe was halted in 2004, prosecutors were not ready to file charges against Allen, due to faulty or unreliable recollections by apparent victims about the dates of their alleged abuse.

"Would we have found something else? Would we have been successful if the investigation went on? I really can't speculate as to that."

More recently, state prosecutors thought they had identified a viable case against Allen for flying a prostitute to anchorage -- a violation of the federal Mann Act.

But the U.S. Department of Justice refused to turn over its files or to deputize state attorneys to proceed with a prosecution on their behalf.

"There was no rationale offered. It was just simply that they were not going to do it. They're not required to explain themselves to us, and to my knowledge they have not."

But U.S. Senator Lisa Murkowski might not take no for an answer.

Her spokesman issued a statement in regard to a federal judge's order concerning an investigation into the prosecution of the late Senator Ted Stevens:

"The senator is examining all the materials released yesterday and is considering taking further action. We're in an information-gathering phase presently, though, and don't want to get ahead of ourselves."

In the meantime, it is unknown whether the federal government allowed a perpetrator of sex crimes back out on the streets.

The Department of Law's request for “cross-designation” for a possible prosecution of Bill Allen under the Mann Act was made a year ago tomorrow.

Deputy Attorney General Rick Svobodny says he met this February with DOJ officials in Washington to pursue the matter.

But the answer remained no.