Born in Marietta, Georgia, Hawk attended the North Springs Charter School of Arts and Sciences, in Sandy Springs, Georgia. While a student, she appeared in the TV series Reality Check. She received a Bachelor of Fine Arts in Theatre from the University of Maryland, College Park in 2004. After a number of small parts in productions including Law & Order: Special Victims Unit, and Across the Universe, Hawk was hired for her role on Blue Bloods. In that show, she plays Detective 2nd Grade Abigail Baker, a member of the Police Commissioner's (Detective) Squad who serves as the primary aide to Police Commissioner Frank Reagan. Hawk's character was introduced in the first season of the series (although Detective Baker's name was shown as "Det. Melissa Baker" in the closing credits, it was changed to "Det. Abigail Baker" in subsequent episodes), in 2010, and thereafter appeared in all but a handful of episodes.

In October 2017, Hawk was a guest of honor at the Spring Gala of HeartShare Human Services of New York, and received the Linda Dano Award. Hawk is married to FDNY Lieutenant Bryan Spies.