Khullar was born in 1964 in Fort Vermilion, Alberta, to teachers who emigrated from India, and was raised in the rural communities of La Crete and Morinville.

She has all acted pro bono at the Supreme Court for the Women's Legal Education and Action Fund in landmark cases Vriend v Alberta and R v Ewanchuk.

[11][12] Vriend led to the inclusion of sexual orientation as a protected right under the Alberta Individual Rights Protection Act and Ewanchuk led to the Supreme Court of Canada ruling that the defense of implied consent is not valid in sexual assault cases, emphasizing the necessity of clear and affirmative consent.

[16] Regarding her elevation to the role, she commented, "the opportunity to serve the people of Alberta, the Northwest Territories and Nunavut in this way is an enormous privilege and responsibility to which I am wholly committed.

"[17] On her appointment, Trudeau wished her success and said: She is a respected member of the legal community and brings a wealth of experience in multiple areas of law to the bench.

A 2023 report from The Advocates Society highlighted that in Alberta, it often takes over nine months to hear short applications and up to two to three years to schedule longer trials.

[21] A proponent of the living tree doctrine and judicial activism, Khullar has advocated for the rights of various protected groups, ranging from those with a disability to those under the LGBT spectrum.

As such, she remarks that legislation of that nature should be given a "broad, liberal, and purposive" interpretation to comply with both national and international standards of constitutional law.