Rep. Darrell Issa and Sen. Charles Grassley sent a letter (pdf) to the Securities and Exchange Commission Thursday requesting additional information on its decision to let former SEC general counsel David Becker participate in the handling of the Bernard Madoff case.

In a letter addressed to Chairman Mary Schapiro, Issa, chairman of the House Oversight and Government Reform Committee, and Grassley, ranking member on the Senate Committee on the Judiciary, criticized the agency’s failure to detect Becker’s conflicts of interest in the matter.