Known for the breakaway reading glasses he uses in the morgue, Hammerback is a New York City Medical Examiner described as an "off-the-charts genius" who only recently traded in a career as a chef to become medical examiner. He has a habit of overtalking and oversharing, and has offered commentary on such unusual behaviors as threesomes and necrophilia, much to the unease of former ME Sheldon Hawkes, who, in one episode, refers to Hammerback's commentary as "going to that creepy place" (episode 301, "People With Money"). Despite any eccentricities on his part, Hammerback sincerely cares for the well-being of his coworkers; he invited Mac Taylor to join his family for their Thanksgiving festivities so the taciturn CSI would not have to spend another holiday alone. He has apparently either known or worked with Mac, Hawkes, and ME Peyton Driscoll for an unspecified number of (episode 205, "Dancing with the Fishes," et al.).

Hammerback nearly dies from a severe allergic reaction to a meatball hero sandwich he ate in episode 317 ("The Ride In") and is saved by the timely intervention of Stella Bonasera, who administers rescue breathing, CPR, and a shot of epinephrine from the first aid kit. When Stella expresses concern that she may have exposed him to HIV, he comforts her, more worried about her own emotional well-being. "I'm sorry I scared you," he tells her contritely.

Hammerback is currently married with two daughters, one about college age (episode 302, "Not What It Looks Like," episode 317, "The Ride In"). Sid has been divorced at least once (episode 304, "Hung Out to Dry"), and celebrated by getting incredibly drunk, after which he fell down the stairs, though he claims he "didn't feel a thing."

Dr. Sid Hammerback has now had the longest tenure as a coroner of the five shown on the series. CSI: NY has also had the most number of coroners of any show in the franchise (CSI has had two coroners and one coroner's assistant throughout seven seasons; CSI: Miami has had one coroner throughout five seasons.)