Fred Thompson (search) will do double duty on two "Law & Order" shows.

Thompson, 62, a former U.S. senator from Tennessee, will continue to play Manhattan District Attorney Arthur Branch on the original series. He also will take the character to "Law & Order: Trial by Jury," (search) the fourth installment of the NBC franchise, which is set to premiere next spring.

"Obviously, Fred is a welcome and quite necessary component of 'Law & Order: Trial By Jury' since the action takes place inside the legal system and he is the district attorney," executive producer and series creator Dick Wolf told The Associated Press Wednesday in an e-mail.

"Law & Order: Trial by Jury" will star Jerry Orbach (search), also of the original "Law & Order" series, as police Detective Lennie Briscoe. The series also will star Bebe Neuwirth (search), Kirk Acevedo and Amy Carlson.

"Law & Order: Trial by Jury" will join "Law & Order," "Law & Order: SVU" and "Law & Order: Criminal Intent."