Unhappy that President Bush won’t dismiss a senior appointee accused of abusing staff and interfering with investigations, Democrats in Congress are planning to haul the official in for public questioning. As the inspector general for the National Aeronautics and Space Administration, Robert W. "Moose" Cobb is supposed to be the top cop at the agency. But a massive investigation by a White House committee into his behavior concluded recently that he had interfered with investigations and deserved disciplinary action "up to and including" removal. "These are serious findings that raise troubling questions as to whether this [NASA] IG office can function effectively under its current leadership," said Rep. Bart Gordon, D-Tenn., Chairman of the House Committee on Science and Technology. Rep. Gordon and Sen. Bill Nelson, D-Fla., have called for Cobb to be dismissed. The two are expected to hold an unusual joint hearing in early May to address their concerns about Cobb, a former White House ethics lawyer. They plan to call Cobb himself to testify. He may face some tough new questions. Privately, Democratic staffers tell ABC News they have new information about the investigation and now believe the final report may have omitted allegations of misbehavior by Cobb that merited inclusion. Click Here for Full Blotter Coverage. NASA employees have filed dozens of complaints about Cobb, charging that he slowed investigations and berated subordinates trying to stop waste, fraud and abuse at the $16 billion agency. "[That's] the kind of thing you would expect to see on ’20/20,’" Cobb told one investigator, according to a redacted version of the final report by the President’s Council on Integrity and Efficiency. The comment was interpreted as a criticism of an investigation showing NASA was wasting millions of dollars storing aircraft and parts it did not need, want or use. The White House panel did not judge each complaint but gave an opinion on Cobb’s conduct overall. NASA administrator Michael Griffin, whose operations and employees Cobb is charged with auditing and investigating, hired an executive coach for the IG, whom he does not manage. Griffin also arranged for him to attend management classes. NASA did not respond to requests for comment. The White House, which has sole responsibility for managing Cobb and other inspectors general, said it endorsed Griffin’s plan. Cobb’s office did not respond to requests for comment.