During the 42nd Canadian Parliament, NDP Leader Thomas Mulcair appointed Hardcastle to be the party's critic for Sports and Persons with Disabilities.

[2] She lost her re-election bid in the 2019 Canadian federal election, having come second in what was considered a surprise upset to the Liberal candidate Irek Kusmierczyk.

[5] A past member of Pathway to Potential and National Pension Reform Committee, she has worked to reduce poverty in Windsor-Essex County and to help more Canadians retire with dignity.

She has organized minor sports programs and tournaments, serving as Direction of the Tecumseh Baseball club and President for the Sun Parlour Female Hockey Association.

She served as an Essex County representative on regional authorities: During the 42nd Canadian Parliament, NDP Leader Thomas Mulcair appointed Hardcastle to be the party's critic for Sports and Persons with Disabilities.