Outside the world of free speech advocacy, most people take the default position that some censorship is necessary and acceptable; that sensible lines can be drawn to keep out the bad stuff without affecting free expression in general. This approach naively ignores one of the great problems with censorship: that it is a tool of power, and once granted censorship powers, the state will almost certainly extend them in directions that could not have been predicted at the start. Thus, any censorship measure is a danger to all expression, and should be greeted with great scepticism.

Sadly, the British people appear to have lost track of this important point. While free expression is protected by the US Constitution, the UK has no such protection in law, and free expression here – especially sexual expression – has been deeply restricted as a result.

It’s not difficult to get the British masses behind new censorship: simply create a moral panic over harm to “women and children” (note that women are not considered to be autonomous adults in such situations). And nothing is better guaranteed to rouse the mob than child abuse.

So it was that in the 1970s, a moral panic (led by the Queen of Panic herself, Mary Whitehouse) over “child porn” led to the Protection of Children Act – which ostensibly existed to criminalise the creation of child abuse imagery. But the law went far further than criminalising abusive imagery: its final wording instead referred to “indecent imagery” – a subjective, moral idea.

In taking the step from child rape to nudity in general, the state sent a message: not that child abuse is wrong, but that the depiction of nudity is wrong, and so the state has enshrined into law an old British attitude – that nudity and sex are synonymous with each other, and naked bodies are dirty and shameful. The law has often been misused – perhaps most famously in 1995 to arrest the newsreader Julia Somerville, and her partner, who had taken photographs of their daughter in the bath. Many other, less famous people, have been branded child abusers and had their lives ruined for taking similar photographs – a victimless crime that upsets the nudity-hating moral attitudes of the British establishment.

The law is also dangerous in defining anyone under the age of 18 as a child. So in theory, a couple aged 17 who take naked photographs of each other – even for private use – can be branded paedophiles and criminalised.

But this is more than just a theory: the law has now been used against teenagers for taking photographs of themselves. A few weeks ago, a teenage girl received a criminal record for sending a topless photograph of herself to her boyfriend. Her boyfriend too was criminalised for having received the image, and in a separate case, a teenager who sent a nude photograph of himself to friends received a caution.

And so a law that was supposedly introduced to protect abused children has instead been used to attack teenagers for enjoying consensual sex lives. It has also absorbed vast amounts of police and CPS resource that could instead have been directed at identifying and rescuing genuine abuse victims. Meanwhile, as we now know, the law did nothing to protect genuine victims of abuse from men in power.

Such is the nature of creeping censorship: laws passed in response to moral panics rarely do what they were intended to do. More recently, as the British censorship state has grown in reach and power, more draconian laws have come into being, and each one covers a far greater scope than promised by the politicians.

The “extreme porn” law is a perfect example of this phenomenon. Introduced in response to the murder of Jane Longhurst (which was dishonestly linked to BDSM pornography), it was supposed to be aimed at avoiding further such murders. Yet, as the law was drafted, it was broadened to include a number of categories of content, including animal porn, for which the vast majority of prosecutions have taken place. Given the broad definition of “possession”, this means that even receiving an unsolicited image is a criminal offence. Recently, two Essex men were found guilty – under a law supposedly designed to protect women from being murdered – for having received an animal porn video via WhatsApp. Although they had not requested the video, and had attempted to delete it, copies had remained on their phones, and they were forced to plead guilty to sexual offences.

And most recently, the “rape porn” law looks to catch far more people who pose no threat to anybody.  The effect of the law is to criminalise consenting adults who enjoy BDSM porn featuring consenting adults.

In each of these cases, a seemingly good cause – child abuse, murder, rape – has been appropriated by the state in order to brand all sexual expression as wrong, as perverted, as criminal. One wonders where the real “perverts” are: at home, watching porn and snapping nude selfies; or in the censorship state, endlessly blurring lines between consensual and non-consensual activities.

Censorship is not something that can be harmlessly introduced to hide “the bad stuff” and leave “the nice stuff” alone. It is harmful by nature, and corrosive to the freedom of everyone. All sexual behaviour risks falling within the remit of Britain’s increasingly draconian anti-porn laws. The state has signalled its belief that all sexual activity belongs at home, in private, behind closed doors, and in the absence of recording devices. And thus, child abusers will cover their tracks and walk free, while consenting adults are branded sexual predators and harassed into taking their kinks back underground.