A conservative group is offering a $100,000 reward to anyone who can show senior White House officials knew about the controversial tactics used in Operation Fast and Furious, the government-sponsored program that knowingly sent guns to Mexican cartels.

A "reward poster" published in Wednesday's Washington Times, reads: "If you have verifiable evidence that President Obama or one of his aides knew about Operation Fast & Furious while it was underway, Call 1-888-692-7374 toll free. This is your opportunity to save yourself before Operation Fast & Furious comes crashing down like Watergate. ... The truth will come out. Will you be caught in the web of Operation Fast & Furious, or will you avoid jail time?"

The reward money was put up by the Conservative Caucus, a grassroots political group. While critics may call it a publicity stunt, the group is defending the move.

Conservative Caucus director Peter Thomas said: "We felt forced to run this advertisement and offer the $100,000 reward because justice was not being served, and we wanted to offer an opportunity to anyone who knows the truth" to come forward.

Attorney General Eric Holder, though, claims he did not know about what was happening in Fast and Furious at the time, nor did top officials at the Justice Department. President Obama claims he did not know nor approve of the operation.

While Congress prepares to pursue a civil suit against the administration for withholding documents, the Office of Inspector General at the Justice Department is expected to release a report in August that will detail who approved and managed the operation and ignored concerns that it was growing out of control.

Also, the Brian Terry family is expected soon to file a wrongful death lawsuit against the federal government -- Terry is the Border Patrol agent killed in 2010, and whose murder scene included weapons from Fast and Furious. The suit will give their attorneys broad subpoena power to obtain testimony and documents Congress did not use. That should include access to line attorneys and supervisory agents the Justice Department shielded from congressional investigators.

While experts differ on whether the Terry family attorneys can force disclosure of documents currently kept secret by the presidents' claim of executive privilege, they do believe a judge would at least require the Justice Department to produce a log of those documents being withheld. This disclosure could provide Congress a powerful weapon in its case, since the administration has claimed a blanket privilege and refused to spell out exactly what they are hiding under executive privilege.