510 ILCS 70/7.1
No owner or person shall confine any animal in a motor vehicle in such a manner that places it in a life or health threatening situation by exposure to a prolonged period of extreme heat or cold, without proper ventilation or other protection from such heat or cold. In order to protect the health and safety of an animal, an animal control officer, law enforcement officer, or Department investigator who has probable cause to believe that this Section is being violated shall have authority to enter such motor vehicle by any reasonable means under the circumstances after making a reasonable effort to locate the owner or other person responsible.
A person convicted of violating this Section is guilty of a Class C misdemeanor. A second or subsequent violation is a Class B misdemeanor.
510 ILCS 70/7.1