Legal definition of mischief
You can be charged with mischief if you hide your wife’s vibrator batteries.
Section 430 of the Criminal Code of Canada sets out the offence of mischief
SECTION WORDING
430(1) Every one commits mischief who wilfully (a) destroys or damages property; (b) renders property dangerous, useless, inoperative or ineffective; (c) obstructs, interrupts or interferes with the lawful use, enjoyment or operation of property; or (d) obstructs, interrupts or interferes with any person in the lawful use, enjoyment or operation of property.
EXPLANATION
The offence of mischief encapsulates situations where property is damaged by an accused. The Criminal Code distinguishes the punishments available based on the financial amount of property that has occurred. Typical situations in which mischief charges arise included young offender graffiti type situations, domestic assault disputes where one party temporarily seizes the property of the other such as a cellular phone or set of car keys, or scenarios wherein a person causes damage to a wall or furniture item as a result of anger. While a wide range of punishments are available at law, it is not atypical for a first time offender who is able to pay restitution to receive a conditional discharge for the offence. That said, for facts that include a repeat offender or significant property damage, jail sentences can and do get imposed.
COMMENTARY
Section 430 sets out the criminal offence of mischief and provides four ways in which the crime can be committed. First, pursuant to subsection (a), the actus reus of mischief can be committed by anyone who "…destroys or damages property." This is a relatively straightforward actus reus mechanism. Typical examples would be smashing a bus shelter, keying a car, smashing a TV. Subsection (b) sets out a slightly more nuanced actus reus of "…rendering property dangerous, useless, inoperative or ineffective." Examples of this would include removing the battery from a car engine or remote control, disconnecting cables on an electronic device, or disassembling an item such that it is no longer capable of performing its intended purpose. Subsection (c) sets out another form for the actus reus of mischief, specifically, any act that "…obstructs, interrupts or interferes with the lawful use, enjoyment or operation of property." This mechanism is quite common in the Criminal Courts. It is not uncommon for an individual to be charged with mischief against jointly held property. Thus, an accused who breaks the remote control cannot resort to the defence that they destroyed their own property, if the property is jointly owned. In this respect, subsection (c) deals with interference with lawful use and enjoyment of property. Examples would include temporarily stealing your spouse's cellular phone, keys or other property. Finally, subsection (d) sets out the actus reus of mischief by way of "obstructing, interrupting or interfering with any person in the lawful use, enjoyment or operation of property." This is drafted somewhat more broadly than subsection (c) and relates to interference with the person in their use and enjoyment of property as opposed to the object itself. The section is a hybrid offence, enabling the Crown to elect to proceed by way of summary conviction of by indictment. The punishments available are found at section 430(3). Notably, subsection 430(2) provides that in cases where the mischief causes actual danger to life, a potential life sentence can be imposed.
STRATEGY
It is not unusual for the police to have pictures of the allegedly damaged property, as well as a witness statement attesting to the fact that the property was damaged by the accused. One of the fertile areas of attack is via the term "wilfully." That is, the Crown must prove that the property was damaged wilfully. This will typically be dependent on witness testimony, which would be subjected to cross examination. Thus, even with pictures demonstrating the damaged nature of the property, and accused could still argue that the property was damaged accidentally, or inadvertently. Consider a situation where in the heat of an argument, a picture frame is damaged. If the facts are such that the frame fell in the midst of a melee, then the argument would be that the frame was merely damaged accidentally, and thus the mens rea component has not been met. Similarly, depending on the facts of the case, the defence could argue that the property in question was already damaged, or that the Crown hasn't proven that the property was not already in that condition prior to the accused's involvement.
http://www.criminal-code.ca/criminal-code-of-canada-section-430-1-mischief/index.html