[1] Hanley played Junior A with the Newmarket Hurricanes before spending four seasons with the UMass Minutemen ice hockey of the NCAA.
[8] He appeared in five games for the Coyotes during the 2017–18 season, as well as 52 for the American Hockey League's (AHL) Tucson Roadrunners.
On May 1, 2019, he made his NHL playoff debut in Game 4 of the Stars' second round matchup against the St. Louis Blues.
[12] On September 10, 2020, Hanley recorded his first career playoff point, assisting on Jamie Benn's goal during Game 3 of the Western Conference Finals against the Vegas Golden Knights.
[13] On September 19, he scored his first career NHL goal in a 4–1 win over the Tampa Bay Lightning during Game 1 of the 2020 Stanley Cup Finals.