Attorneys for a former Mafia boss who might face the death penalty in an upcoming trial expressed dismay Wednesday at the unsealing of court documents that reveal their client, Vincent Basciano, is under investigation for a potential plot to kill a federal judge.

The attorneys, James Kousouros and Ephraim Savitt, said they would ask for an evidentiary hearing into the alleged plot against Eastern District Judge Nicholas G. Garaufis, which Kousouros said did not exist. Kousouros said it was “very unfortunate” that he was not notified by federal prosecutors that the document was going to be made public late Tuesday evening.