A Republican, Smullen has represented the 118th district of the New York State Assembly, covering parts of the North Country and Mohawk Valley, since 2019.

[1] He was a White House Fellow in the Office of the Secretary of Energy in 2003 and 2004, and more recently worked as the executive director of the Hudson River–Black River Regulating District.

[3] In April 2018, after longtime Republican Assemblyman Marc W. Butler announced his retirement, Smullen launched his campaign for the 118th Assembly district.

[4] Smullen defeated businessman Patrick Vincent in the Republican primary, and bested Democrat Keith Rubino in the November general election with 63% of the vote.

[6] Maintaining that the double filing had been a mistake, Smullen pleaded guilty to a reduced charge in May 2019 after he paid back the town of Niskayuna for the missing property tax.