Warning: Contains spoilers for The Lincoln Lawyer season 1.
Netflix's Ther Brass Verdict and who gives protagonist Mickey Haller a mentor figure to consult for advice. The former partner of Haller's deceased father, a successful attorney who Haller looked up to, Siegal serves as a stand-in for the senior Haller.
The addition of Elliott Gould's character is a major departure from The Lincoln Lawyer books. In Michael Connelly's popular series, Haller was younger when his father died, only 5 years old. With no memory or direct connection to his father, the book's Mickey Haller Jr. learned about both the law and his father by studying books about the great Mickey Haller Sr.
Elliott Gould's cameo takes the Netflix adaptation in another direction from The Lincoln Lawyer books. Instead of relying on the difficult to portray notion that Haller's knowledge of his father and the legal system comes from books, Siegal's presence is a living link to Haller's father. This addition can cut down the amount of narration provided by Haller, and provides an opportunity for a larger role for Gould in The Lincoln Lawyer season 2.
A defining feature of the book's Lincoln lawyer is that he operates out of his Lincoln cars, not an office. In Netflix's adaptation of The Lincoln Lawyer, Haller works out of an office. However, the Lincolns do serve an important purpose. Throughout season 1, the car is consistently used as a setting for Haller to explain various important aspects of the legal system. He uses his driver Izzy Letts, another of The Lincoln Lawyer's character changes, as a sounding board and stand-in for viewers who aren't well versed in civil and criminal procedure. It's a useful device and serves the show well. Certain technical details about jury selection, for example, have a direct bearing on the plot, but aren't necessarily common knowledge. However, excessive narration can slow down the pacing and feel unnatural at times. The addition of Elliott Gould's character provides an alternative, as he conveys important legal context in a more conversational manner.
Elliott Gould could return to fulfill the same role, providing additional legal knowledge and perspective to Haller in The Lincoln Lawyer season 2. While Haller is known for his ingenuity and natural talent, the series so far lacks the book's explanation for how he grew into the lawyer that he is today, besides the vague notion that he looked up to and decided to emulate his father. Elliott Gould's character helped to give Haller more depth by showing a side of Haller that was still seeking guidance and hinting at how he became the accomplished and principled lawyer that he is. A recurring role for Elliott Gould in The Lincoln Lawyer season 2 could further enrich Haller's character as he is mentored by the closest thing he still has to the father that inspired him.