Morishita was first elected in Brooks city council in 1998 at the age of thirty. He was elected Mayor of Brooks in 2016 and president of the Alberta Urban Municipalities Association in 2017. In September 2021, he stepped down from both roles to become leader of the Alberta Party after the resignation of former party leader Stephen Mandel. He ran in a by-election for the southern Alberta seat of Brooks-Medicine Hat on November 8, 2022 but lost to the UCP candidate, Alberta premier Danielle Smith.
