Updated

While reviewing expense reports for a 2000 construction project, a bookkeeper for Alaska oil services giant VECO Corp. asked for an explanation. Who was this work for, she asked? Why was it performed?

The cryptic note she received back included the instruction, "No paper trail."

Federal prosecutors say the note, introduced as evidence Friday at Sen. Ted Stevens' corruption trial, was part of a scheme by Stevens and VECO founder Bill Allen to conceal more than $250,000 in home renovations and other gifts that the contractor bestowed on the Senate's longest-serving Republican.

Bookkeeper Cheryl Boomershine testified Friday that VECO employees submitted invoices and expense reports for a project located in Girdwood, a ski town south of Anchorage where VECO didn't normally work.

When she requested details, she said she got little information back. The note listed only one reason for the secrecy: "per Bill Allen."

The unusual project was a dramatic renovation of Stevens' home and it has become the centerpiece of his gift-giving trial. Prosecutors say he withheld the free renovations from his Senate disclosure forms.

The 84-year-old Stevens, a Senate powerhouse for generations, has seen both his influence and re-election prospects weakened by the case. His lawyers say he was a busy senator who couldn't oversee every aspect of the project but who, like every homeowner, paid the bills that came in — $160,000 in all.

But VECO employees testifying Friday painted a picture of a project that was far from normal. They described being pulled off their regular jobs and being dispatched to the senator's house.

"We were working 10 hours a day, six days a week," said Roy Dettmer, a VECO electrician who said he overhauled the electrical system, installed electrical fixtures and rewired the house.

Dettmer estimated he worked 400 hours on the job at a rate of up to $29 an hour, plus overtime. Every morning, he said, he clocked in at another VECO job site, then headed out to work on the senator's house.

Other employees said they installed a custom steel staircase, a balcony, a new roof and more.

Prosecutors say Stevens didn't pay for any of that work. The only bills he paid were for an independent carpenter, and authorities say he must have known that didn't cover the whole project.

Stevens' lawyer says his client was in the dark about the renovations project and blamed his friend Allen for "devious" gift-giving that landed the senator in trouble. Since he had no idea he was getting free work, Stevens says, he couldn't have disclosed it on Senate forms.

To press that point, Stevens lawyers asked the VECO employees how often they saw Stevens and his wife at the house. The workers said the couple was there rarely, if ever.

As for the billing documents, Boomershine acknowledged under cross-examination by the defense that it was Allen who signed off on them and Allen who apparently asked for the secrecy.

Allen has pleaded guilty to bribing Alaska lawmakers and is the government's star witness against Stevens. He is expected to take the stand Monday and cross-examination could be the key to the senator's defense.