Since then, she says, she has spoken in person with one of the 50 or so analysts who came forward to claim their conclusions were changed. The congresswoman also reviewed some of the documents that were allegedly changed, she says, confirming her concerns.
"I have reason to believe that analysis was doctored in a manner that made the impression that the intelligence was a reflection of a more positive outlook in Iraq than was justified," she said.
Speier would not identify the analyst with whom she spoke other than to say he was not from California. She also declined to specify what documents she read.
"I think this was a very serious charge that was leveled by a whistleblower within the IC (intelligence community)," Speier said. "He is someone who has been doing this job for multiple decades, and my evaluation based on interviewing him is that he is very credible."
On Friday, House Republican leaders announced the creation of a task force to investigate allegations that senior U.S. Central Command officials manipulated intelligence. Republicans on the Intelligence, Armed Services and Appropriations committees are leading the task force, which is expected to deliver preliminary results next month, according to Jack Langer, a spokesman for Rep. Devin Nunes, chair of the Intelligence panel.
That investigation will also focus on whether the analysts' allegations "reflect systemic problems across the intelligence enterprise in CENTCOM or any other pertinent intelligence organizations," the chairmen of the three committees said in a statement.
Speier said she's also concerned about a more widespread problem.
"We'll have to take steps to make sure that the information that is shared up the chain and to the president and to the committees of jurisdiction is, in fact, the unvarnished truth," Speier said.
The Pentagon's inspector general launched an investigation into the allegations in September.
A CENTCOM spokesman said in a statement that Army Gen. Lloyd Austin, who heads the command, is "taking these allegations very seriously, and we welcome the independent oversight on this matter."