In April 2010, Collins and Senator Joe Lieberman issued a subpoena seeking documents and interviews associated with the American government's investigation into the conduct of investigators during their interactions with Nidal Hasan before the Fort Hood shooting. The Pentagon announced that the Obama administration would not authorize Senate investigators to question intelligence agents who reviewed e-mails between Hasan and an extremist Islamic cleric before the shooting. Collins and Lieberman issued a statement accusing the Departments of Justice and Defense of refusing "to provide access to their agents who reportedly reviewed Major Hasan's communications with radical extremist cleric Anwar al Awlaki and to transcripts of prosecution interviews with Hasan's associates and superiors, which DOD already provided to its internal review."