When "Goliath" films on the street in front of Chez Jay and the Ocean Lodge, no layer exists between cast, crew, and the public. Billy Bob Thornton frequently stops and takes pictures with tourists as he's very happy to interact with his fans.
David Cross, who's typically known for his comedic roles, excelled in the more dramatic performances on set. After he would do a couple of takes, the director would let him have another to improvise a bit.
The restaurant location in the scene where Billy and Patty meet with Jeff Clayton was supposed to be filmed at another restaurant, but the deal fell through at the last minute. Previously during a location scout of the area, the production team had been to breakfast at El Tepeyac, which is a staple of Boyle Heights. The producers called the owners of that restaurant that night, asking if they could shoot there the next day. The owners agreed and let them shoot after hours.
Costume designer Lindy McMichael found a white suit for Gabriel (Manuel Garcia-Rulfo). The suit was too big and its pants were too short. She insisted on using it anyway--removing his socks and finding the perfect shoes--to bring his character to life in a unique way.
The method Billy uses to badger Detective Roman-- having a friendly conversation with the suspect's wife until the suspect comes home--was a trademark method of Lt. Columbo (Peter Falk) in the series "Columbo."