51. Every owner or lessee of a place where an offence under a provision of this Act is committed who authorizes or allows the commission of the offence therein is liable, in addition to costs, to a fine equal to that prescribed for the offence which he has authorized or allowed.
Every owner or lessee of a motor vehicle who authorizes or allows the commission, by means of the vehicle, of an offence under a provision of sections 4 to 12, 31, 32, 38 and 39 is liable, in addition to costs, to a fine equal to that prescribed for the offence which he has authorized or allowed.
In proceedings brought under the first or second paragraph, evidence that an offence under a provision of this Act was committed by a person in the employ of such owner or lessee shall be, in the absence of any evidence to the contrary, proof that the person committed the offence with the authorization or consent of the owner or lessee.