Matthew L. LaMountain is an American attorney and politician serving as a member of the Rhode Island Senate for the 31st district.

His mother was a substitute teacher and his father worked for the United Parcel Service.

[2] LaMountain served as a prosecutor in the Rhode Island Attorney General's Office from 2011 to 2019, specializing in cybercrime and digital evidence.

From 2019 to 2021, he served as assistant city solicitor for the Warwick, Rhode Island.

LaMountain also operates an independent legal practice, specializing in criminal defense litigation.