BOSTON (AP) — The judge in the public corruption trial against Salvatore DiMasi and two associates has instructed the jury to convict only if they believe the government has proven that payments were made in exchange for official acts taken by the former Massachusetts House speaker.

The jury began deliberations Monday.

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U.S. District Court Judge Mark Wolf also said jurors should give particular scrutiny to the testimony by former software salesman Joseph Lally, who cooperated with prosecutors in a deal that could net him a lighter prison sentence.

WBZ NewsRadio 1030’s Lana Jones reports

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The defense argues the government’s case is “built on a foundation of quicksand” because it relies heavily on Lally’s testimony.

The government alleges DiMasi used his clout to assure software firm Cognos received two state contracts worth a combined $17.5 million in exchange for payments, with DiMasi pocketing $65,000.

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