The Los Angeles Institute is the Institute located in Los Angeles, California. It is located inside a church, on a hill near the Pacific Coast Highway. It was last managed by Arthur Blackthorn, and secretly by his nephew Julian.
After the war, the young Blackthorns—save Helen and Mark—were allowed to remain at the Institute when Arthur became their new legal guardian. The Institute also became home to a ward, Emma Carstairs. In 2008, Cristina Rosales arrived to stay at the Institute when she turned eighteen and was shortly after followed by the Centurion Diego Rosales.
The death of Arthur worked in favor for the Cohort, who had been targeting the Institute, which they suspected had weak leadership under Arthur's deteriorating health. They hoped to have Horace Dearborn take over the Institute to potentially give him power to propose the Registry as a Law.
The floor of the Institute entryway is made of black and white marble that forms a mural that depicts the shape of the Angel Raziel rising from Lake Lyn, holding the Mortal Cup and Sword. This image was created as a memorial to the Shadowhunters who died during Sebastian Morgenstern's attack on the Institute in December 2007. The entryway is also decorated with uncomfortable-looking furniture that no one ever uses.
Right across from the entrance is a large staircase that leads to the upper floors. Located at the very center, it divides the Institute into its north and south wings. Most of the Blackthorns' rooms are found in the south wing, while Emma chose a bedroom at the other end.
The Institute's library is smaller than those of other Institutes, but it is renowned for its large collection of books in Greek and Latin. It is said to have more books on the magic and mysticism of the classical period than the Vatican City Institute. The library used to have terra-cotta tile and Mission windows, but it was destroyed during Sebastian Morgenstern's attack. Now, the library has been rebuilt with a starkly modern design; it is made of glass and steel, the floor polished mountain ash, and there are protective spells guarding the library. At the top of the library is a large skylight that is closed with a large copper lock and decorated with protective runes. Maps are kept in a chest that bears the crest of the Blackthorn family and the family motto: Lex malla, lex nulla ("A bad law is no law").
On one of the upper floors is an art studio. It consists of two rooms: the larger one is for the general use of every member of the Blackthorn family, while the smaller room is Julian's private space—one he has only shown Emma—which has a lock on the door at all times. Julian's mother, Eleanor Blackthorn, used the larger room as a studio and the smaller one as a darkroom when she was alive, and the studio is still decorated with her brightly colored abstract art works.
- This is the primary setting of The Dark Artifices.