PROVIDENCE — The first week of former Lincoln Town Administrator Jonathan F. Oster’s bribery and conspiracy trial ended Friday with the state laying the groundwork it hopes will show that Oster and ex-Planning Board member Robert R. Picerno tried to extort money from people wanting to buy a piece of land the town controlled.

But the defense used prosecution witnesses to make some of its points, particularly that the land Oster is accused of selling at a too-low price might actually have so much industrial contamination as to have a negative value, making any offer, no matter how low, a good one.

Friday’s testimony ended early when one of the jurors reported feeling ill; the case is set to resume tomorrow morning. Oster is facing two counts of bribery and two counts of conspiracy. He is accused of conspiring with Picerno to shake down two different potential buyers of the land in 2001.

In his 2004 trial, Picerno pleaded no contest to four counts of taking, or trying to solicit, bribes, and three counts of conspiracy to solicit bribes for his part in the alleged scheme.

On Friday, the state explained the troubled history of a 6-acre piece of land at the center of its case, the H&H Screw Co. land on Route 116.

Though the H&H Screw property had a good location on a popular road, former town solicitor Mark Krieger testified Friday that concerns over who would be responsible for the possible multimillion-dollar cleanup bill had prevented Oster from taking title to the land, even though the town could have because no one had paid taxes on it for nearly a decade.

When Oster took office in 2001, the old H&H building was occupied by Banneker Industries, which had been there since 1991. Banneker owner Cheryl Snead told of how her original landlord stopped accepting her rent checks in 1993 and told her to send them to the town. She sent the checks to the town, but they came back uncashed.

Krieger testified that the concern on the town’s part was that if it accepted a rent check, it might be designated the owner of the land, and made to pay for the cleanup.

Leon A. “Lee” Blais testified Thursday that he kept Oster apprised of his research into the site. When he told Oster about the cleanup costs, he said Oster told him local car dealer Robert Campellone had expressed interest in acquiring the land. Campellone is one of the men the state says Oster and Picerno sought bribes from to buy the land.

Blais testified that Campellone was offering $50,000 for the site. Blais said he thought the offer too low. He also wanted to know the cleanup costs first and said he thought a car dealership was a bad fit for that part of Route 116.

Besides establishing the history of the parcel, prosecutors tried to show that Oster and Picerno had political and financial ties. Michael Hill, Oster’s campaign treasurer, testified that a fundraiser that he had described as “organized and orchestrated” by Picerno brought in $10,655 of the $43,284 that Oster collected for his 2000 town administrator campaign.

Krieger and Blais testified that they were uncomfortable about the access Picerno seemed to have to all parts of Town Hall, and both said they told Oster to rein him in. Both also testified that when pressed, Oster told them Picerno was an important fundraiser for his campaign.

Blais, who left the Oster administration in the middle of 2001 to pursue a legal career, said he remembered going up to Oster at the Lodge, a Breakneck Hill Road bar popular with town political types.

“I basically used a raspy voice and characterized Mr. Picerno as Darth Vader,” Blais said.

jhill@projo.com