An Alaska businessman who was the key witness in the corruption trial of former Sen. Ted Stevens is under investigation by local and federal authorities over allegations he had sex with underage girls in the 1990s.

Bill Allen, the founder and former CEO of oil services company VECO, has been under investigation by Anchorage police since last year over allegations he engaged in sexual relations with at least two 15-year-old girls in the mid-1990s. The age of consent in Alaska is 16.

A report in the Anchorage Daily News details allegations by Lisa Moore, a former girlfriend of Allen, that Allen had a sexual relationship with a 15-year-old girl in 1996, and that he potentially attempted to cover up the relationship when it appeared it would be made public. Moore says when her brother got into legal trouble and it appeared Allen's alleged sexual conduct would be revealed in court, the businessman sent Moore, her brother and her fiance to California, to avoid a subpoena.

Moore was evidently introduced to Allen by a roommate of hers who was working as a prostitute. Moore says she informed Anchorage police of Allen's sexual activities in 2004, and it appears that prosecutors in former Alaska Sen. Ted Stevens' 2008 trial were aware of the allegations, but used Allen as a key witness all the same.

Sen. Stevens was charged in 2008 with seven counts of failing to report gifts, a felony. The case involved claims that Allen's company, VECO, had renovated Stevens' Alaska chalet at a cost of $250,000, a gift that Stevens had failed to disclose.

Stevens was convicted in October, 2008, days before the election that would see Stevens lose his seat to Democratic challenger Mark Begich. In the spring of 2009, Attorney General Eric Holder submitted a motion to set aside Steven's guilty verdict, in light of allegations of prosecutorial misconduct in the case. The courts accepted Holder's motion and Stevens' conviction was vacated.

Among the facts to emerge were that Allen had told prosecutors at one point that the actual value of the work done on Stevens' home was closer to $170,000, but that testimony never made it to court.

The latest allegations against Allen cast further doubt on Allen's credibility as a witness, the ADN reports. In 2007, Allen and a vice-president at VECO pleaded guilty to charges of extortion, bribery and conspiracy to impede the IRS. It was during the investigation into those crimes that the Stevens home remodeling came to light, leading to the prosecution of Stevens.

The latest allegations against Allen cast a further cloud of corruption and criminality on Alaska's political scene, as Allen was one of the best-connected businessmen in the state. In 1997, the Anchorage Chamber of Commerce named Allen one of the five most influential people in the state, along with Stevens, Sen. Frank Murkowski, then-Gov. Tony Knowles and then-Anchorage Mayor Rick Mystrom.

Read the whole report at the Anchorage Daily News here.

View the ADN's timeline of events here.