It's kind of a trick question. Because the whole point of the Obama "extend and pretend" policy was to pretend that the banks are financially sound (when they're not) and if they actually did do a study showing their precarious financial situation and it got out, that would present certain problems. So Sen. Warren has boxed them in nicely with this approach:

The U.S. Department of Justice appears to have neither conducted nor received any analyses that would show whether criminal charges against large financial institutions would harm the economy, potentially undermining a key DOJ argument for why the world’s biggest banks have escaped indictment.

Testimony by a top Justice official and fresh documents made public on Wednesday during a House financial services committee hearing revealed that financial regulators and the Treasury Department did not provide warnings to prosecutors weighing the economic consequences or fallout in the financial system of criminal indictments against large financial groups. DOJ also could find no records that would substantiate its previous claims that it weighed potentially negative economic or financial impacts when considering criminal charges, said Mythili Raman, acting assistant attorney general for the criminal division.

Wednesday’s revelations are likely to increase criticism of the Obama administration, which has been accused of a lackluster enforcement record against big banks in the financial crisis and other matters.It also may put further pressure on the Justice Department to strengthen future prosecutions. Recently, instead of filing criminal charges against large financial groups, federal prosecutors have begun to file criminal cases against subsidiaries. Observers including lawyers at Weil, Gotshal & Manges LLP, a top defense firm, have warned that Justice may expand its limited use of criminal indictments in part due to public pressure.