Roper v Knott  1 Q.B. 868
Absence of Malice - Malicious Injuries to Property Act 1861
Knott was a milk salesman who worked for Roper. Knott came every morning and collected four gallons of milk from Roper’s place of business. Following complaints as to the quality of the milk, one morning, Roper and a police officer watched Knott as he proceeded to pour water into the milk which he intended to sell on to his customers. The entire portion of milk had been spoiled and this was to the value of 10s and 8d. The magistrate was of the opinion that Roper had acted fraudulently to increase the bulk of milk to sell on and keep profits.
An important issue in this case was whether Knott could be convicted under the Malicious Injuries to Property Act 1861, section 52. The earlier case of Hall v Richardson (1889) held that a milk carrier who damages employer's milk by adding water to it, with no intention of injuring his employer, but in order to make a profit for himself, is guilty of an offence under the Malicious Injuries to Property Act 1861, section 52. The important question on this basis was whether Knott had damaged the milk ‘wilfully or maliciously’.
The court had no doubt that Knott had wilfully damaged the milk and this was with the fraudulent motive of gaining an advantage for himself. The judges held that the decision in Hall v Richardson could not be followed due to error and therefore the appeal must be allowed. The case was subsequently remitted to the magistrates to convict Knott.