Assault is defined as the intentional application of force to another person without that person's consent. The application of force can either involve actual contact, either directly or indirectly, or it can be the result of a threat where there is a reasonable belief that the person has the ability to presently carry out the threat. The charge of assault does not require that there be any injury or harm done, although where the contact is so trifling as to be considered incidental, the charge of assault would not be made out.
Consent cannot be obtained through the application of force or the threats of force to the victim or another person. Nor can it exist in a situation through the exercise of authority (i.e. a boss cannot order an employee to consent). The mental state of the victim may also negate the presence of consent. Examples of this would include a person who is mentally handicapped and does not understand what they are truly consenting to, or a person who is intoxicated to the point that it is interfering with their decision making capabilities.
The sentence for an assault will depend on whether the Crown proceeds by way of summary conviction or indictment. In most cases, the Crown would likely proceed by summary conviction before the Ontario Court of Justice. In this case, the maximum penalty would be 6 months custody, although a sentence as low as an absolute discharge would be available. If the Crown proceeds by indictment before the Superior Court of Justice, the maximum penalty is 5 years custody.