The Sexual Offences Act 2003 (UK) includes offences of exposure of the genitals, voyeurism, and sexual activity in a public lavatory. In addition, there are offences concerning engaging in sexual activity in the presence of a child and causing a child to watch a sexual act. However, the most relevant case law deals with the first limb of the common law offence of outraging public decency ; the question of whether the act is of such a lewd character as to outrage public decency.
 The historical origins of s 125 indicate there are links with the common law offence of outraging public decency. Smith and Hogan noted in the first edition of the text Criminal Law that “[t]he most common way of committing this offence is by indecently exposing the body”. The observations of Lord Simon in R v Knuller (Publishing, Printing and Promotions) Ltd are also helpful in illustrating the types of situations encompassed by what his Lordship considered was “a general rule whereby conduct which outrages public decency is a common law offence”. Lord Simon observed:
Secondly, the decided cases look odd standing on their own. Indecent exposure (Rex v. Crunden  EngR 147; (1809) 2 Camp. 89), acts of sexual indecency in public (Reg. v. Mayling  2 Q.B. 717), indecent words (Reg. v. Saunders (1875) 1 Q.B.D. 15), disinterring a corpse (Rex v. Lynn (1788) 2 Durn. & E. 733), selling a wife (cited in Rex v. Delaval  EngR 90; (1763) 3 Burr. 1434, 1438), exhibiting deformed children (Herring v. Walround  EngR 9; (1681) 2 Chan.Cas. 110), exhibiting a picture of sores (Reg. v. Grey  EngR 41; (1864) 4 F. & F. 73), procuring a girl apprentice to be taken out of the custody of her master for the purpose of prostitution (Rex v. Delaval: see also count 4 in Reg. v. Howell and Bentley (1864) 4 F. & F. 160, 161, conspiracy to procure a girl of 17 to become a common prostitute) — all these have been held to be offences. They have a common element in that, in each, offence against public decency was alleged to be an ingredient of the crime (except Grey, where it was said to be “disgusting and offensive”, “so disgusting that it is calculated to turn the stomach”).
 In terms of the type of conduct that is encompassed by the common law offence of outraging public decency , we can begin with R v Mayling which is perhaps a classic illustration of what is encompassed by the offence. It involved two men masturbating in a public lavatory. Two police officers watched a man go into the toilet and walk out looking disgusted. They then walked into the toilet and caught the appellant masturbating. The appellant argued that the act of indecency had to have in fact “disgusted and annoyed” those “within whose purview the behaviour was committed”. The Court did not accept that submission finding that an objective test applied to the question of whether the act was sufficiently outrageous.
 The same approach was applied in R v May but there the issue was whether the acts were in public. That case involved a school teacher who asked two 13 year old students to instruct him to do various degrading sexual acts such as simulating sex on the desk. The facts of the case indicated that the students did this initially only at the request of the schoolmaster, but with time began to do so on their own volition because it “amused the boy[s] to humiliate the schoolteacher”.
 The two appellants in R v Gibson were charged with committing an act outraging public decency in relation to a model with an earring made of freeze-dried human foetuses of three to four months gestation which was exhibited in an art gallery. Their convictions were upheld.
 In R v Hamilton the taking of photographs was seen to be capable of comprising an act outraging public decency. The defendant put a camera in his backpack, went into a supermarket and put the backpack in a position where he could point the hidden camera up the inside of a number of women’s skirts. None of the women saw him filming, nor did anyone else in the store see what he was doing.
 There has been some debate about whether the offence of outraging public decency continues to serve a useful purpose. However, the Law Commission of England and Wales reviewed the position recently and recommended the retention of the offence. The Commission noted that a random sample of 47 prosecutions in 2014 found this offence was used for:
(1) exposure of genitals (8 cases);
(2) masturbation in public (21 cases);
(3) real or simulated sexual activity in public (8 cases);
(4) making intimate videos without consent (“upskirting”) (8 cases).
Two cases did not fall into any of these categories: one involved a sexual assault and the other involved making child pornography, and in both cases other charges were brought in addition to outraging public decency.
The NSW Law Reform Commission in its 1992 Discussion Paper 24 - Blasphemy commented at 4.38
It is an indictable offence at common law for a person to commit in public an act of such a lewd, obscene or disgusting nature as to amount to an outrage to public decency, whether or not it tends to deprave and corrupt those who see it. Cases have centred on indecent exposure, but the offence is not so limited and some conduct presently punishable as blasphemous would fall within this definition. Indeed, the most recent English case to deal with the offence of outraging public decency relied heavily on Whitehouse v Lemon, the leading blasphemy authority