The 55-year-old actor will play Jimmy McArthur, who questions the SVU squad's motives during a hate crime-rape investigation, reported the New York post.
Baldwin has a long and volatile history with the media.
The star, who lives in the Village, called a reporter for a "toxic little queen" last June after it reported that Baldwin's wife, Hilaria, was tweeting during the celebrity-packed funeral of 'The Sopranos' star James Gandolfini.
The episode will go on air on March 19.