Who is Lieutenant Hans Rollenberger from The Concrete Blonde and what is their importance?

Promoted to the Robbery Homicide Division shortly after Harry Bosch was demoted following the Dollmaker shooting, Rollenberger is a cookie-cutter bureaucrat. He is a climber and avoids controversial or career-threatening decisions. In RHD, he quickly earned the moniker "Hands Off" as a result. Rollenberger is brought in to lead the team of investigators looking into the Follower killings, and when Bosch conducts his illegal search of Ray Mora's home, Rollenberger is beside himself with the thought of the consequences. Therefore, instead of informing Assistant Chief Irvin Irving, he allows Harry Bosch to creatively get them out of the close call.