[2] Leslyn Ann Lewis[3] was born in Jamaica, and she immigrated to Canada at age five and grew up in East York, Ontario.

[4] Lewis graduated with a Bachelor of Arts with high distinction from the University of Toronto as a student of Trinity College.

[8][9] Lewis began her political career in the riding of Markham—Stouffville, where she was vice president and a primary fundraiser of the Conservative electoral district association while Paul Calandra was MP.

[14][15] In February 2020, Lewis was confirmed as an official leadership contestant for the Conservative Party of Canada,[16] following the resignation of Andrew Scheer as leader in December 2019.

[23] On August 25, 2020, Lewis announced that she would be running for a seat in the House of Commons in an undisclosed riding in the 2021 Canadian federal election.

As CBC reported the matter, "Notably absent from the critics' list are MPs who have voiced opposition to COVID-19 vaccine policies.

In February 2023, Lewis, along with fellow Conservative MPs Colin Carrie and Dean Allison, had dinner with Christine Anderson, a Member of the European Parliament representing Alternative for Germany, who was on a Canadian tour of right-wing media and convoy protest supporters.

The meeting was condemned by the Centre for Israel and Jewish Affairs, the Canadian Anti-Hate Network, and Prime Minister Justin Trudeau among others, for Anderson and AfD's Islamophobic and antisemitic positions.

[38] In January 2024, Lewis officially authorized a House of Commons e-petition for Canada to withdraw from the United Nations and UN-affiliated groups such as the World Health Organization and promoted it on her social media.