Billy Bob Thornton liked including the late John Ritter in his films (Sling Blade, Bad Santa) and now John Ritter's son Jason appears in Goliath.
Both the Ocean Lodge Hotel (where Billy lives) and the Chez Jay bar (where Billy drinks) are real places in Santa Monica, California. The interior of Chez Jay, however, was too small to accommodate a cast and camera crew, so an expanded version was replicated on a studio soundstage. Chez Jay was only used for the exteriors.
Season one showrunner David E. Kelley chose to feature the Santa Monica 'Chez Jay' bar because that's where he first met his wife, Michelle Pfeiffer.
The opening theme is Bartholomew by The Silent Comedy. The song has also been featured in S01E08 of The Originals (2013) and in a trailer for the video game Dark Souls (2011).
Both Harold Perrineau (Judge Keller) and Tania Raymonde (Brittany Gold) starred in the TV series Lost (2004).
Early in the pilot as Billy (Billy Bob Thornton) is trying to persuade daughter Denise (Diana Hopper) to attend Indiana University, he reels off random names of the university's celebrity alumni, Ernie Pyle, Hoagy Carmichael, Lee Majors, Bobby Knight, Dick Enberg, David Anspaugh, Joe Buck and Jane Pauley. Denise is unimpressed.