Played by Clyde Kusatsu

Judge Mike Matsumura presided over the singing twins custody case in episode 3x10 [The Nutcrackers].

Clyde Kusatsu
Veteran character actor Clyde Kusatsu has been performing on television since 1974, when he appeared in episodes of Ironside and Mannix. His long list of credits includes several previous roles as judges, including in a 1987 episode of LA Law, in the 1994 James Spader film Dream Lover, and in two episodes of The Practice, as Judge Stephen Chin. The Hawaiian-born Kusatsu also appeared on several episodes of Magnum PI in the 1980s with Tom Selleck. His other Boston Legal connections include appearances on TJ Hooker (1985) with William Shatner, Designing Women (1992) with Delta Burke, The Adventures of Brisco County Jr (1994) with Christian Clemenson, and David E. Kelley shows Chicago Hope (1998) and Ally McBeal (2000). He also had a recurring role as Admiral Nakamura on Star Trek- The Next Generation. Kusatsu's recent credits include episodes of The Closer, Numb3rs, Charmed, Monk, and Shark. He also has a current role on the daytime drama The Young And The Restless. Kusatsu has also done a vast amount of voice-over work for animated programs.

Clyde Kusatsu at the Internet Movie Database
Clyde Kusatsu at Wikipedia