Cox was sworn into the Maryland House of Delegates on January 9, 2019. He was a member of the Judiciary Committee, serving on its family law and public safety subcommittees from 2019 to 2020 and its family and juvenile law and civil law and procedure subcommittees from 2021 to 2023. In his first term, Cox filed 84 bills, only two of which passed (both of which were introduced in 2019), and attached amendments to others.
