You should not leave a child unattended in a motor vehicle for any length of time. If children are trapped inside cars—especially in hot weather—they can suffer from heat exhaustion or heat stroke in a matter of minutes, leading to permanent disability or death. Heat stroke, also known as hyperthermia, can cause shock, seizures, irregular heartbeat, and heart attack, as well as brain, liver, and kidney damage. Leaving a child unattended in a car is also a form of neglectful supervision that is investigated by Child Protective Services.

In Arizona, it is illegal to leave a child unattended in a motor vehicle according to state statutes. Specifically, Arizona Revised Statutes § 13-3623 addresses circumstances under which a person having custody of a child can be charged with child abuse if they leave a child unattended in a vehicle if such conditions may cause substantial risk to the child's health or safety. Arizona's hot climate makes the risk of heat-related illnesses like heat stroke particularly severe. If a child is found to be left in a car, especially under conditions that could lead to heat exhaustion or heat stroke, it can be grounds for a charge of child abuse. Additionally, such an act can be considered neglectful supervision and may be investigated by Child Protective Services (CPS). Penalties for leaving a child unattended in a vehicle can range from fines to more severe criminal charges, depending on the circumstances and the outcome of the child's condition.