WASHINGTON - The White House answer to "who knew what and when?" shifted again today as White House Press Secretary Jay Carney told reporters that Chief of Staff Denis McDonough and "other members of the senior staff" knew about the investigation into the IRS's targeting of conservative groups last month.

While President Obama said he only learned about the IRS targeting after the story broke on May 10, several of his top advisors knew about it more than two weeks earlier.

Carney said today that White House Counsel Kathy Ruemmler was told on April 24 that the IRS Inspector General "was finishing a report" about "IRS employees improperly scrutinizing" organizations applying for tax exempt status by using words like "tea party and "patriot." Ruemmler then informed McDonough and other members of the president's senior staff, Carney said.

That seems to contradict what Carney said last week both about who was informed of the investigation and what they were told.

"My understanding is that the White House Counsel's Office was alerted in the week of April 22nd of this year, only about the fact that the IG was finishing a review about matters involving the office in Cincinnati," Carney said on May 13. "But that's all they were informed as a normal sort of heads up."

And on May 14, Carney said: "We found out about it just a few weeks ago, and only - and when I say 'we,' I didn't, the president didn't, but the White House Counsel's Office only found out about the review being conducted and coming to conclusion by the Inspector General."

Today Carney said it would have been inappropriate for the White House to take action before the report was finalized and released and there was no need to inform the president.

"We knew the subject of the investigation and we knew the nature of some of the potential findings," Carney said. "But we did not have a copy of the draft report, we did not know the details, the scope or the motivation surrounding the misconduct, and we did not know who was responsible."