Martin Maycock is the Chief of the Los Angeles Police Department, after having worked as a detective with the Robbery-Homicide Division. He and Harry Bosch came up through the ranks together and worked on the Dollmaker Task Force. Maycock was a more astute politician than Bosch and thus rose higher in the ranks. He presumably served at Lieutenant, Captain, and Deputy Chief. However, it is unclear why he is not mentioned in any of Bosch's cases until 2011. Over time he became more of a politician and bureaucrat than cop and became less popular with the troops. After assuming the office of the Chief, Maycock acquired the unflattering nickname of "Marty MyCock."
In 2012, anticipating the 20th anniversary of the Rodney King riots, Chief Maycock ordered all unsolved murders from the riots to be reopened. This led to Bosch reopening the case of Anneke Jesperson. When Bosch began to make some headway with the investigation, Maycock became concerned that Jesperson might be the only riot-related cold case to be cleared - a white woman known as Snow White. He believed this would not sit well with the community, so he told Lt. Cliff O'Toole to give Bosch a new case and have him back off Jesperson until after the 20th anniversary had passed. Of course, Bosch refused to take the new case or back off Jesperson. Maycock and Bosch had a confrontation.