Heather Mason is a former federal prisoner and for the past 5 years, she has been advocating for criminalized women on a variety of prison issues, including segregation, strip-searching, conditions of confinement during the COVID-19 pandemic, and the issue of prisoners transferring from male prisons to women’s prisons. Her advocacy on this latter issue connected her to a group of women who formed a grassroots organization focused on maintaining women’s rights to single-sex spaces called Canadian Women’s Sex-based Rights (CaWsbar).