Three House committees subpoenaed in connection with the bribery case against jailed former Rep. Randy "Duke" Cunningham are trying to reach an agreement with federal prosecutors allowing the subpoenas to be withdrawn.

Wednesday was the latest deadline for the Appropriations, Armed Services and Intelligence committees to respond to document subpoenas issued by the federal grand jury in San Diego that has been considering evidence in a defense contracting investigation stemming from the Cunningham case.

However, House lawyers have asked for more time and are working to negotiate a response that satisfies prosecutors so that they will withdraw the subpoenas, a Democratic aide said Wednesday. The aide spoke on condition of anonymity because of the sensitive nature of the negotiations.

A spokeswoman for the U.S. Attorney's Office in San Diego did not immediately return a call for comment.

Cunningham, a San Diego-area Republican, was sentenced in March to more than eight years in prison for accepting $2.4 million in bribes in exchange for steering government business to defense contractors.

The San Diego grand jury has been considering evidence against Brent Wilkes, a defense contractor identified as one of Cunningham's coconspirators.

The subpoenas were issued late last year when Congress was still under Republican control. The Democrats who now run the House want to cooperate while also safeguarding constitutional prerogatives that shield federal lawmakers from prosecution while they're engaged in legislative acts.

The Justice Department has clashed with Congress in the past over its investigations of lawmakers. Republicans and Democrats alike were furious when the FBI raided the office of Democratic Rep. William Jefferson of Louisiana in May for evidence in a corruption investigation.