Why are some immigration detainees held in a CBSA facility and others in a provincial jail?

CBSA operates its own immigration holding centres, generally intended for detainees who don't present a higher-risk profile, and these facilities are meant to be less restrictive in character than a correctional institution, reflecting the fact that immigration detention is an administrative measure rather than a criminal punishment. Not every region has a CBSA holding centre, and capacity and location also affect where someone actually ends up.

Provincial correctional facilities tend to be used where a higher security level is considered necessary, often connected to a serious criminal history, specific danger-to-the-public concerns, or behavioural issues that a CBSA holding centre isn't equipped to manage, as well as in regions where no dedicated CBSA facility is available at all. Being held in a provincial jail alongside the general criminal population is a significant, and for many people distressing, aspect of detention that can be raised as part of the broader release argument at a review.

Because where someone is held can itself become a relevant factor at a detention review, particularly if it raises concerns about proportionality or conditions, anyone detained in a provincial facility should get legal advice about whether a transfer or release addressing this specifically can be pursued.