He was a small business owner who ran a company making fences before joining the general assembly.

[2] He did not run for re-election in 2014 and was succeeded by Reggie Phillips, and he returned to the Illinois House after the 2016 elections.

[4] Because of the number of people and jobs that have left Illinois, Halbrook says that he is committed to reforming worker's compensation laws by eliminating unnecessary regulations.

[7][8] During his time as a state legislator, he voted in favor of bills to provide transparency for local governments.

[4] Republican Governor Bruce Rauner endorsed Halbrook and, in addition to several independent groups, spent money in support of his campaign.