DETROIT (CBS Detroit/AP) — Testimony in the corruption trial of former Detroit Mayor Kwame Kilpatrick turned Thursday to his father’s involvement in a major sludge contract, with testimony that Bernard Kilpatrick — among other things — accepted a case of Cristal as a bribe.

James Rosendall, a representative of Synagro, was a witness for the federal government Thursday. He says he repeatedly paid cash to Bernard Kilpatrick to protect a $1 billion sludge deal between Detroit and Synagro Technologies.

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The Houston company was hired in 2007 to recycle wastewater sludge and build an incinerator. But the deal collapsed when it was disclosed that Rosendall paid bribes to win council approval.

He pleaded guilty in 2009.

Rosendall says he flew Kwame Kilpatrick and others to Las Vegas in 2003 on a private jet at a cost of $20,000. He says he also contributed to Kilpatrick’s campaign and other causes to gain favor.

Rosendall testified he once stuck $300 in a gum wrapper and delivered it to Bernard Kilpatrick because he said he needed money to buy his grandkids Christmas presents.

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In further testimony against Bernard Kilpatrick, FBI hidden cameras were rolling when Kilpatrick allegedly scolded a businessman for trying to hand him $2,500 cash at a restaurant table. “You know I don’t want anybody to see me taking money from anybody,” Kilpatrick said, according to the recording.

The Kilpatricks and a third man are accused of extortion, bribery and other crimes.

Former Wayne County Deputy Executive Mike Duggan, who is exploring a run for Detroit mayor, was mentioned in the audio recordings played by the prosecution in court. On tape, Bernard Kilpatrick
accuses his former bosses in the county of “borderline illegal” deals.

Duggan says he’s not sure what Kilpatrick is referring to.

“There is no telling what Bernard Kilpatrick might have said to a client he was trying to get money from, but I have always operated by the book, I always will,” Duggan said.

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Duggan, who says he has not been contacted by the U.S. District Attorney’s office regarding the corruption trial, says no one has accused him of any wrong doing.