The applications, which are under a federal court’s seal, were given to Issa by a mole with access to the documents. Issa has claimed they reveal that top-level Justice Department officials signed off on the documents and knew about the controversial “gun-walking” tactics used in Fast and Furious. Issa has called his source a “whistleblower” and refused to disclose his or her identity.   

“The enclosed wiretap affidavit contains clear information that agents were willfully allowing known straw buyers to acquire firearms for drug cartels and failing to interdict them — in some cases even allowing them to walk to Mexico,” stated a letter Issa sent to his panel’s ranking member Elijah Cummings (D-Md.), which was put into the record on Thursday.

“In particular, the affidavit explicitly describes the most controversial tactic of all: abandoning surveillance of known straw purchasers, resulting in the failure to interdict firearms.”