Who is Maxim Andreyevich Erchov from The Case of Comrade Tulayev and what is their importance?

Erchov is the High Commissar for Security and Commissar of the People for Internal Affairs. He is forty years old and in very good health but prematurely wrinkled. He has puffy eyelids, thin lips, and uneasy eyes. He is charged with the impossible task of coming up with the terrorists who plotted to kill Tulayev, when he is fairly certain it was the act of an isolated individual. Erchov himself is arrested on his way back from vacation and eventually confesses to crimes he did not commit in order to remain loyal to his country. He is executed.