According to the City of Ottawa, crossbows can be fired within city limits. However, better read the fine print: crossbows are classified as firearms, and as such, their use is severely restricted. They are not only banned from use in almost every urban part of Ottawa, but they cannot be used in any area where other people might be present — that includes public lands, schools, parks, roads, recreation centres, and churches. In fact, the bylaw specifically states that crossbows cannot be fired within 200 metres of any place of worship (even in non-urban areas where discharging a crossbow would otherwise be considered legal). A relic from medieval times? Not really, since it merely pertains to the avoidance of people.
Even if your property falls within a geographical area where a crossbow is allowed to be used and all other criteria are met, you must still meet all of the hunting and discharge of firearms requirements set out by Ontario’s Ministry of Natural Resources. Moreover, only certain animals, at designated seasonal times, can be hunted. There are hunting exemptions, though, for farmers within city limits (think coyotes in North Gower) and municipal officers looking to scare away sick or vicious animals, like that moose that wandered into a Rockland schoolyard last year. Of course, the latter two are not likely using crossbows.
So before you get all trigger-happy and thwack off a few bolts at that pesky varmint chewing up your garden, you might want to ask yourself, is it really worth it? Violations of related city bylaws and provincial hunting laws result in fines and possibly imprisonment.