Harrigan began her rugby career in Grade 9 at Medway High School.

[2] Harrigan was named in the Canadian team that competed in the Pacific Four Series in New Zealand.

[3] She was called into the Canadian squad for the delayed 2021 Rugby World Cup as a late replacement for Laura Russell, who had been ruled out due to injury before the tournament began.

[4][5] In 2022, Harrigan received a two-month suspension from World Rugby after testing positive for the banned substance spironolactone.

[4][6] The drug was administered by her family physician without obtaining a therapeutic use exemption, although the violation was deemed unintentional.