Simpson Thacher & Bartlett has overbilled the federal government nearly $100,000 for work related to the U.S. Department of the Treasury’s Troubled Asset Relief Program, according to a special inspector general’s report released Wednesday.

The so-called SIGTARP’s latest quarterly report to Congress — which also details the TARP–related fees paid to 12 other Am Law 200 firms — comes the same week as the publication of a new book in which the four-year-old program’s first special inspector general, Neil Barofsky, chronicles what he says was a failure by regulators to curtail Wall Street’s excesses.