Glen was first elected to represent the Last Mountain-Touchwood Constituency for the Saskatchewan Party in 1999. He was re-elected in 2003, 2007, 2011 and 2016. During his two terms in opposition, Glen's critic duties included Post-Secondary Education, Highways and Transportation, Environment, Labour, Deputy Critic for Aboriginal Affairs and Deputy Critic for Culture, Youth and Recreation.
Following the 2007 election, Glen would serve as Chair of the Legislature's Standing Committee on Human Services and later as Deputy Chair of the Legislature's Standing Committee on Public Accounts.
Glen is currently Deputy Speaker of the Legislative Assembly and serves as a member of Treasury Board, the Private Bills Committee and the Crowns and Central Agencies Committee.
Glen and his wife Marlene have three children and ten grandchildren.