NBC reported that some letters and subpoena notices issued by James Comer, which were sent out in connection to his investigation into Biden’s use of the so-called autopen, bore a digital signature. Comer has sent 16 letters to former Biden White House officials requesting transcribed interviews, NBC said. Metadata analysis showed that all appeared to be signed with a digitally inserted signature. Comer’s apparent use of a digital signature now threatens to cloud Republicans’ efforts. A spokesperson for the House committee on oversight and reform, the body Comer heads, said using a digital signature for correspondence was common practice.