An investigation by an intelligence committee in the Senate found that the U.S. Central Intelligence Agency used brutal methods of interrogation that turned out largely useless results and then lied about the effectiveness of the tactics, according to a leading Washington newspaper.

The Senate report, as described in the newspaper article, contradicts the defenses of the torture program during the Bush-era. The defenses were that harsh interrogation methods were needed in order to produce results and that the torture program itself was responsible for saving lives of Americans by foiling terrorist attacks.

In truth, the CIA overstated the program’s effectiveness and hid the harshness of methods the program used. Intelligence breakthroughs that were credited to CIA enhanced interrogation methods were instead received through different means and then the agency sued them to bolster its defenses of their torture program. The intelligence committee will vote on Thursday on whether to declassify the report.

The report is now the center of a dispute of high profile between the CIA and the Senate. Dianne Feinstein, the committee chair weeks ago publicly accused the CIA of breaking laws and violating the U.S. Constitution by spying on staff from the Senate that was conducting the same investigation.

The CIA counters her accusations by accusing staff from the Senate of gaining access that was unauthorized to information that was classified. That charge was called absurd by Harry Reid the Senate Majority Leader.

Currently the Department of Justice is looking at both allegations.

A key part of the differences between the Senate and CIA is an internal review in the CIA that was ordered by Leon Panetta, the director at the time.

Feinstein said the review bolsters the Senate report’s conclusions regarding the torture program used during the Bush-era and it undermines the rebuttal by the CIA that contends the report from the Senate contains errors in facts.

The newspaper report notes that officials had been troubled by the discrepancies between senior officials’ statements in the CIA in their communications with employees at a lower level that were directly involved.

Those communications that were written might explain why Panetta’s internal review could have contradicted high praise the program was given in public by officials from the CIA and Bush defenders.