Tom Shayes, a graduate of Yale Law School, is Patty's senior legal associate and most-trusted advisor. His paternal demeanor and unassuming air make him a natural confidant for Ellen. Patty pretends to fire him in order to allow Ellen to become her new protégée for easier manipulation results. While "unemployed," he is offered a partnership position at a rival law firm, a move that causes the clients in the Frobisher lawsuit to seek to fire Patty and hire Tom as their lawyer. Eventually, Patty meets the rival firm's offer to Tom, minus one detail (changing the name of Hewes & Associates to include his name in the title), causing Tom to return to the fold. Tom is now an equal partner in the law firm. While working on the Tobin case, Tom makes an unwelcome discovery and will stop at nothing to set things right. Shayes clerked for Supreme Court Justice Sandra Day O'Connor and is a vegan.
Tom was one of the victims of the Tobin's fraud, as he and his in-laws had invested money with an investor who had invested with the Tobins. Tom was killed by Joe Tobin, as seen in the season 3 finale "The Next Ones Gonna Go in Your Throat"