The offence of common nuisance is outlined in section 180 of the Criminal Code.
A person commits a common nuisance when they commit an illegal act or fail to execute a legal duty and thereby endanger the lives, safety, health, property, or comfort of the public, or obstruct people from exercising or enjoying their rights. Committing a common nuisance becomes an offence when the common nuisance endangers the lives, safety, or health of the public or causes physical injury to a person.
Person A knows she has HIV and is not treating it but does not execute her legal duty to disclose this before donating blood.
Person C intentionally urinates into the water jug at a community event and does not tell anyone, causing many people to continue drinking from it.
R. v. Thornton (C.A.), 1991 CanLII 7212 (ON CA)
In R. v. Thornton (C.A.), the accused was charged with common nuisance when he donated blood to the Red Cross after twice testing positive for HIV.
Offence Specific Defence(s)
No Offence or Legal Duty
Where the person does not commit an illegal act, does not have any legal duties to execute, or does not fail to execute a legal duty, they will not have completed the offence of common nuisance.
No Danger, Obstruction, or Injury
Where a person commits an illegal act or fails to execute a legal duty, but this does not cause the lives, safety, health, property, or comfort of the public to be endangered and does not cause physical injury, they have not completed the offence of common nuisance.
Only Affecting Individuals
Where a person’s illegal action or failure to execute their legal duty only endangers the life, safety, or health of an individual or a small group of people and does not physically injure anyone, they may not have completed the offence of public nuisance. For example, if person A neglects to feed their child, and this only endangers the life of that child, person A may not have completed the offence of public nuisance.