He has been self-employed since the age of twenty as the owner of several small businesses, including PM Productions, a video store he created while in college, and the Dedham Community Theatre, which he currently owns and operates.

[7] His involvement in this issue was complicated by his dual role as both a state representative and a local business owner, prompting questions about potential conflicts of interest.

[9] In 2008, McMurtry became a central figure in a heated legislative battle to grant Wegmans supermarket a beer and wine license at the planned $1.5 billion Westwood Station development.

[10] McMurtry encountered strong opposition from fellow representatives, notably Angelo Scaccia and William C. Galvin, who cited concerns over increased traffic and competitive disadvantages for existing businesses like Roche Bros.[11][12] In 2018, McMurtry was one of the original sponsors of Bill H.4479, which placed restrictions on e-cigarettes and raised the age for buying tobacco from 18 to 21.

[13] Citing the increasing vaping epidemic among youth, McMurtry sponsored the bill in able to "prevent young people from taking up the deadly habit and getting addicted to nicotine products".

The same year, McMurtry filed legislation to protect independent auto repair shops against vehicle manufacturers.