The first week in the corruption trial for former Nassau County Executive Ed Mangano and former Oyster Bay Town Supervisor John Venditto is in the books.

Prosecutors laid out their case against the officials and Mangano’s wife Linda – who is accused of accepting a no-show job that paid her $100,000 per year.

MORE: Prosecutor: Mangano, Venditto ‘earned their keep’ for bribes, kickbacks
MORE: Newsday's Joye Brown on Singh's testimony
MORE: All eyes turn to Harendra Singh as corruption trial nears
MORE: Jury seated as Mangano, Venditto corruption trial gets underway

Defense attorneys have painted the prosecution’s star witness, restaurateur Harendra Singh as a liar who made a deal with the federal government to protect himself.

Singh testified Thursday that in the mid-1990s, he quickly learned that he would have to “join the club” if he wanted to succeed in business. Singh says he joined the Bethpage Republican Club, and became fast friends with elected officials and political up-and-comers, like Mangano and Venditto.

“They were not only friends that he enjoyed spending time with, but they were also friends that were useful to him,” says Newsday’s Andrew Smith.

When Mangano announced his candidacy for Nassau County executive in 2009, Singh says he quickly contributed to his friend's campaign in cash and other ways.

Singh testified that his family owned the entire building at his flagship restaurant, Singletons. He said when Mangano ran for county executive, he rented him an office inside the building at well below market value. He says campaign workers ate at his restaurant "day and night" and racked up a bill of more than $50,000. Singh said he significantly discounted those meals.

After Mangano's victory, Singh testified that the county executive-elect handed him a printout of a $3,000 office chair. Singh said he understood that to mean he was expected to buy it for his friend, which he did.

When Singh needed the Town of Oyster Bay to guarantee millions of dollars in loans to keep his restaurant empire afloat, he says he asked Mangano to reach out to Venditto.

Singh said the group discussed the topic at a Nassau GOP fundraiser in 2010. He said his “investments" in Mangano, Venditto and others ensured he had access to power, and his loan guarantee was granted.

Attorneys for the three defendants mostly declined to comment on Singh's testimony Thursday. The prosecution's lead witness will take the stand again Monday.