Steve Mason

He is the FBI director and a member of the SPK. He helped L in the Kira's investigation sending FBI agents to Japan but gave up after all the agents were killed by Kira. He was too a leading Near's employees who helped to convince the U.S. President to form the SPK.

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Later, along with other members of the SPK, he was killed by Mafia who used the Death Note (by Jack Neylon from Mello's orders) to show that Mello was better than Near.