What’s more, a long-anticipated report on WaMu by the Inspector General offices of the FDIC and the OTS is expected to be released soon, according to the Treasury Department.

“WaMu is a political nightmare,” said Stephen Klein, an attorney at Seattle-based law firm Graham & Dunn.

“The question in this case is, Did the FDIC seize the bank prematurely? It’ll be interesting to see politically how that’s handled.”

Killinger’s testimony is expected to be the most dramatic. He is expected to say that government officials turned their back on the century-old Seattle institution in the months before they seized it because WaMu was not part of an elite “club” of Wall Street bankers.

The former chief executive, who was ousted three weeks before WaMu was closed, plans to point to the Treasury Department’s refusal to place the bank on a list of financial institutions that were off limits to short-sellers during the summer before its closure, a move that would have helped support WaMu’s plummeting stock price at the time, according to people familiar with the testimony.

Killinger also was expected to discuss the changes in federal laws in the weeks following WaMu’s seizure that allowed the government to bail out other large financial institutions, these people said.

Both Killinger and Rotella plan to devote a large part of their testimony on efforts to reduce home-loan lending and exposure to risky mortgage loans starting in 2005 and until the bank was seized.

The bank’s foray into subprime and option ARM (adjustable rate mortgage) lending is the subject of an extensive shareholder lawsuit under way in federal court in Seattle. The lawsuit claims that WaMu executives allowed an out-of-control lending environment to flourish at branches across the country, according to court documents. All executives named in the case have filed motions to dismiss it.

Killinger plans to take responsibility for actions that occurred on his watch and also in the home-loan group, and to discuss WaMu’s purchase of California subprime lender Long Beach Mortgage in 1999, according to people familiar with his testimony. Many of WaMu’s bad loans originated at Long Beach.

Killinger, however, will assert that executives were turning the ship around. He is expected to illustrate that the bank had cut its home-loan originations from $384.2 billion in 2003 to $100.9 billion in 2007. Option ARM originations also dropped during that time, according to Killinger’s planned testimony. Its subprime portfolio, meanwhile, increased between 2003 and 2005, before executives began to cut back.

Rotella’s planned testimony also will focus on the bank’s efforts to rid itself of its risky mortgages.

But he also is expected to point out that many of the decisions to expand in that direction occurred before he joined as president in 2005, according to a person familiar with his testimony. Rotella, who was also chief operating officer, plans to point to efforts he made to diversify the bank’s portfolio and shed its exposure to the worsening real estate market, including shaking up the management of Long Beach Mortgage and selling about $140 billion of mortgage servicing rights.

Both executives are likely to face pointed questions, particularly because the bank’s subprime loan exposure continues to be blamed for the bank’s closure.

The subprime portfolio “was too big and too messy,” said Jim Bradshaw, who covered WaMu for more than 15 years at brokerage D.A. Davidson & Co.