El Chenier was born in 1967 in Toronto, Ontario, Canada. They hold a BA from York University (1992) in Toronto, and a MA (1995) and PhD (2001) in History from Queen's University in Kingston, Ontario. From 2001-2003 they were a postdoctoral fellow at McGill University and taught in the Women's Studies program from 2003-2004. They were appointed Assistant Professor in Simon Fraser University's History Department in 2004 and have been an associate faculty member of the Gender, Sexuality and Women's Studies Department since 2008.

Their MA thesis, "Tough ladies and troublemakers: Toronto's public lesbian community, 1955-1965," was an oral history of butch and fem lesbian bar culture in post-World War Two Toronto. An article based on this research was published in Left History as "Rethinking Lesbian Bar Culture: Living 'the Gay Life' in Toronto, 1955-1965," and has been reprinted in four editions of the edited reader "Rethinking Canada: The Promise of Women’s History." Their PhD dissertation, "Stranger in our midst: Male sexual 'deviance' in postwar Ontario," was published as a monograph in 2008 by the University of Toronto Press under the title "Strangers in Our Midst: Sexual Deviancy in Postwar Ontario." They have published numerous academic articles on various subjects relating to the history of sexuality, including those on debutantes and elite femininity in interwar Montreal, same-sex wedding ceremonies, and on interracial relationships and marriage. They have received numerous Social Sciences and Humanities Research Council research grants for her work. In 2010, they founded the Archives of Lesbian Oral Testimony (ALOT) as a way to digitize, preserve, and disseminate their own oral history research, along with that of others.