Glen was first elected to represent the Last Mountain-Touchwood constituency for the Saskatchewan Party in 1999. He was re-elected in 2003, 2007, and again in 2011. During his two terms in opposition, Glen's shadow cabinet duties included Post Secondary Education, Highways and Transportation, Environment, Labour, deputy for Aboriginal Affairs and deputy for Culture, Youth and Recreation.

Following the 2007 election, Glen served as the Chair of the legislature’s Standing Committee on Human Services and deputy Chair of the legislature’s Standing Committee on Public Accounts. Glen has served as a member of the legislature's committee on Human Services as well as the caucus’ standing policy committee on human services. Glen is currently Deputy Speaker of the Legislative Assembly.

Glen and his wife Marlene have three children and nine grandchildren.