Larry Gandle is the supervisor of the Homicide Special Section of the Los Angeles Police Department's Robbery-Homicide Division. As of 2007 he held the rank of Lieutenant, and he supervised Harry Bosch and his partner at that time, Ignacio Ferras. He is not the worst supervisor Bosch has ever had, but he is also not especially effective.
In 2009 he was still Bosch's supervisor and attempted to oversee the investigation into the murder of John Li, but Bosch's typical investigative style kept Gandle in the dark most of the time. When Bosch went to Hong Kong to rescue his kidnapped daughter, Gandle did nothing to keep the Li investigation moving. To be fair, Gandle was hampered by the fact that Ignacio Ferras only wanted to handle paperwork, and Bosch's de facto field partner was David Chu, a detective that Gandle did not supervise. They had suspect Bo-Jing Chang is jail, and Gandle was content to rely on that.
After Bosch's return, two Hong Kong detectives visited Gandle with the intent of taking Bosch back to Hong Kong for prosecution. Gandle could have told them to go away unless they had extradition papers. Instead he called Harry into a meeting to answer the charges. The focus of the Li investigation then shifted dramatically to the Robert Li who was under surveillance by Ferras. Gandle said he wanted to ride with Bosch and Chu to arrest Robert Li, but before they could get there Mia-ling Li shot and killed Ferras.
In 2010 Gandle had a peripheral involvement in the Jason Jessup case, mostly on 8 April when Jessup escaped and was being sought.
By 2014 he had been promoted to Captain. While working on the Bonnie Brae arson case, Bosch picked the lock on the door of Gandle's office in order to get access to the robbery books that were stored there. Gandle had a surveillance camera installed in his office because of repeated thefts from his collection of pens. Gandle took the video to Capt. Crowder and Lt. Samuels for disciplinary action.
In the series Gandle is a Captain and the commanding officer of Hollywood Division. He replaces Harvey Pounds who was transferred after an altercation with Detective Harry Bosch. Gandle makes a point of meeting Bosch when he returns from suspension and points out that he was lucky that Sergeant John Mankiewicz was a witness and spoke up for Bosch, confirming that Pounds initiated the fight. Bosch is unrepentant and Gandle backs off.
Gandle is eventually replaced as Captain of Hollywood Division by Ellen Lewis.