Federal defenders, who have already faced criticism from the Pennsylvania Supreme Court and a federal judge over their tactics, are now being asked to explain themselves to the U.S. Supreme Court.

In refusing to review the death sentence of Michael Ballard, who pleaded guilty in 2011 to killing four people, including his ex-girlfriend, in Northampton County, the court took note of a letter from Ballard complaining about the federal defenders’ attempts to get involved in his case.