Born in New Mexico, United States,[1] Haines and her family then moved to India where they lived for six years before returning to North America.

Whilst volunteering on a medical humanitarian mission to post-Ebola Liberia, she produced a documentary highlighting the plight of chimpanzees that were abandoned following years of experimentation by a U.S. research laboratory.

On 12 October 2017, CTV announced on social media that Haines had accepted a job as a co-host and correspondent on its news magazine, W5.

The documentary includes an exclusive, chilling interview with a cartel leader – a risky and difficult to organize a journalistic coup.

[12] This W5 investigation into who left 11-month-old Dusty Bowers to die in the snow forced the Ontario Provincial Police to reopen this 30-year-old cold case.

[14] The documentary investigated a preacher who made headlines for defying public health laws during the COVID-19 pandemic, sending shockwaves through a small Ontario town.

Pastor Henry Hildebrandt from the Christian Fundamentalist Church of God emerged as a hero to the anti-lockdown crowd, preaching against the government, police, and the medical community over public health restrictions.

[20] In 2018, Haines was nominated for two RTDNAs for documentaries shot by herself in Liberia and Iraq: 'My Penpal: The Warlord's Wife'[5] and 'Two Kilometres to Terror: Life and Death Under ISIS'.

[13] In 2022, Haines won the Canadian Screen Awards for 'Best Host or Interviewer, News or Information' for her work on the W5 documentary "A Town Divided.

Both Avery and Emily are daughters of Paul Haines, poet and librettist of Escalator over the Hill, which was co-written with Carla Bley.

Haines retaped the segment, but later that day, a CTV technician mistakenly aired the tape that included the error and the comment.