Before you start going around with a firearm in your vehicle, you should contact your provincial Wildlife Dept. first. While you may not be breaking a criminal law, you would probably be in violation of Wildlife regulations.
In Newfoundland, you are not permitted to have in your possession a firearm in an area where wildlife is present, (which is practically everywhere) without having either a hunting licence or a Permit to Transport from the Wildlife Dept. I believe that most other provinces have similar regulations. Penalties for this are heavy, and a conviction would also mean the forfiture of the weapon, and a ban from hunting.
Should you have a recognized need to have a firearm in such areas, ( bear protection for example ) a Conservation Officer can issue you a special permit for this.
Transporting a firearm inside an urban area may be exempt from Wildlife regulations, but you best check it out first.