In Sherras v De Rutzen (1895), the Defendant was convicted of supplying liquor to a policeman on duty. The defendant regularly sold liquor to off duty policemen and the office in question didn't have an armlet which implied he was off duty. The court noted that another section made it an offence to knowingly harbour or suffer to remain on his premises any constable on duty. The court imported this similar requirement despite the absence of any mens rea word in that subsection.
In Alphacell v Woodward (1972), the company had a factory on the banks of a river where they produced manilla fibres, every weekend a man was supposed to inspect the pumps in case they overflowed. However of a period of time the pumps overflowed and released pollution into the river, the company was convicted of causing polluting matter to enter a river, despite the presence of the pumps and the man whose job it was to inspect them.
The company maintained they had not been negligent, The House of Lords held if a stature creates an offence or causes something to happen then if reasonable people would say he defendant caused then no mens rea is required. The house of lords felt that it was very important to prevent the pollution of rivers so the 2nd ground of their decision was that it was an issue of social concern. In Smedleys Ltd v Breed (1974), A housewife had found a caterpillar in one of the cans of peas she had bought, The caterpillar had gone undetected whilst processed.
The magistrates, although finding Smedley's had exercised all reasonable care was nevertheless guilty of the offence of strict liability. Where an offence is one of strict liability, the prosecution must still prove that the defendant committed the actus reus, if the defendant acted involuntarily then there is no actus reus and so the defendant can be held liable. The defendant has a defence of automatism to driving offences if it is not proven that the defendant was actually driving.
On the other hand if an offence is one of absolute liability, even the lack of a voluntary act by the defendant will not allow them to avoid liability this was shown in R v Larsonneur (1933), The defendant had gone to Ireland when her permission to be in the UK had expired. She was deported from Ireland and returned to England against her will despite this, she was found guilty of "being an alien to whom leave to land in the UK has been refused". A defence of due diligence may be available in certain situations, the burden of proof is on the defendant to establish the defence.
In some cases the defence is combined with a third party defence requiring the defendant to prove both. This defence was relied upon in Tesco Ltd v Nattrass (1972), A washing powder was advertised on sale at 14p but its true price was nearer 19p. The company blamed the store manager for not checking the shelves thoroughly. The House of Lords held that the company was entitled to rely upon the defence. There have been some social benefits claimed and injustices caused by strict liability.
In the case of Warner illustrated above, it was a crime of strict liability to be in unauthorised possession of drugs. This is a social benefit to the public, because it convicts people who many endanger others. In Gammon (1985), Lord Scarmen confirmed that a presumption of mens rea is required before a person can be convicted of a criminal offence. In the case of Lim Chin Aik (1963), The defendant had been convicted of remaining in Singapore after having been denied entry.
He had not known about the prohibition which had not even been published, his conviction was then quashed, The case was one of injustice because the defendant had no idea that he was committing an offence of strict liability. In the case of Pharmaceutical society of GB v Stockwain Ltd (1986), the defendant has supplied drugs on prescription which were allegedly signed by the Doctor, however they were forged. The company had not acted intentionally, recklessly or negligently, but the House of Lords held the offence was one of strict liability.
This case again caused injustice because the company were not to blame, it was only the actions of one person who worked for the company that were reckless. Strict liability cannot be justified because it results in the conviction of person who have behaved impeccably and how should not be required to alter their conduct in any way, in the case of Callow v Tillstone the butcher would not have done anything else and yet he was still guilty of strict liability.
Strict liability is also unjust, even if an absolute discharge can be given the defendant may feel rightly aggrieved at having been formally convicted of an offence that he was not responsible for. In addition a conviction may have consequences outside the courts upon the defendant's reputation. With strict liability, the thoughtless and inefficient are negligent, still strict liability is not that these persons are penalised but that others who are completely innocent are also liable to conviction.
Lord Devlin in Reynolds v Austin (1951), stated that strict liability should only apply when there is something that the defendant can do to promote the observance of the law- which comes close to requiring negligence. If there was something which the defendant could do to prevent the commission of the crime and which he failed to do, he might generally be said to have failed to comply with a duty – perhaps a high duty or care and so have been negligent.
Another reason why strict liability can never be justified is in Alphacell v Woodward, Lord Salmon thought the relevant statutory section "encourages riparian factory owners not only to take reasonable steps to prevent pollution but to do everything possible to ensure that they do not cause it" This suggests that however vast the expenditure involved and however unreasonable it may be in relation to the risk, the defendant is under a duty to take all possible steps.
Yet it is doubtful whether factory owners will in fact do more than is reasonable and it is questionable whether they ought to be required to do so. The contrary argument is that the existence of strict liability does induce organisations to aim at higher and higher standards. Strict liability cannot be justified by the amount of time and money spent on going to court, there is little administrative advantage. Also with strict liability better alternatives are available, the defence to cases should be diligence and not negligence.