The Hill News

A resolution approved by the Senate Thursday night has authorized the staff of embattled Sen. John Ensign (R-Nev.) to testify before a federal grand jury investigating the lawmaker's alleged criminal misconduct.

Ensign is accused of violating federal rules in finding lobbying work for Doug Hampton, the husband of the former campaign staffer with whom he was having an affair.

Without special permission, staffers are prohibited by Senate rules from testifying outside of Congress.

Ensign colleague and former campaign adviser Sen. Tom Coburn (R-Okla.) said July 24 that he had provided emails for the Justice Department's probe.

The Senate ethics committee is also investigating Ensign, whose term expires in 2012.