In Franz Kafka’s novel, The Trial, the protagonist Josef K. is unexpectedly arrested by two unidentified agents from an unspecified agency for an unspecified crime. For the duration of the story, neither Josef nor the reader knows what he is supposed to have done, even when he is eventually killed for his crime.

The situation surrounding Pakistan’s controversial blasphemy laws is not dissimilar. The law means that anyone found guilty of defaming the Prophet Muhammed can be sentenced to death. Many facing such accusations have been forced into hiding or killed by mobs before they even stand trial.

Blasphemy laws in and of themselves are not unusual: many countries across the world have legislation which restricts what one can say about religion. The problem in Pakistan comes from the exceptionally harsh penalties, and the light burden of proof. The law sets out no guidance on what constitutes blasphemy, no standards for evidence, no requirement to prove intent, and no safeguards to punish those who make false allegations. This means that, essentially, the standard for blasphemy is whatever offends the accuser. As such, it is frequently used to persecute minorities or settle personal vendettas.

Witnesses can refuse to repeat the alleged blasphemy in court, in case they themselves become culpable. There have been stories of judges refusing to hear evidence defending the accused for fear of offending religious zealots. Blasphemy is a non-compoundable crime, meaning that cases cannot be settled out of court. Once a charge is filed, it is difficult for the case to be quashed, and the accuser cannot simply drop charges. It is not unthinkable that someone could be accused of blasphemy and sentenced to death without ever being told exactly what they are meant to have said and thus being unable to disprove it. Suddenly, Kafka’s Josef F doesn’t seem quite so surreal.

That blasphemy laws are a serious impediment to freedom of speech goes without saying. But the extent to which this is true has been highlighted yet again in recent days, with the news on 21 February that Sherry Rehman, Pakistan’s ambassador to the US, is under police investigation over allegations of blasphemy.

The basic facts of the case are as follows. In late 2010, before Rehman had been posted to the US, she lodged a private members' bill seeking to abolish the death penalty for blasphemy after Aasia Bibi, a Christian woman, was sentenced to death. Two other politicians who were campaigning for a change to the law were murdered soon afterwards. Salman Taseer was shot in January 2011, and Shahbaz Batti in March 2011. Blasphemy reform was shelved soon afterwards.

On 30 November 2010, before Rehman’s private members' bill had been thrown out, she appeared on Dunya TV’s news programme, Dunya Meray Aagay. She repeated her calls for the law to be re-examined and for the death penalty to be removed. Remarks she made on the show prompted Muhammad Faheem Akhtar Gill, a marble dealer in Multan, to lobby police to register a case against her for blasphemy. After nearly three years of persuasion, his efforts have been successful, and the police have started an investigation under the orders of the Supreme Court. Given the aforementioned problems with the blasphemy legislation, the media cannot report what Rehman is supposed to have said, in case newspapers fall foul of the law. People are clearly curious: a Google search for “Sherry Rehman - what did she say” yields 21,800 results.

That a lawmaker should face a criminal investigation for discussing a parliamentary matter is, once again, Kafkaesque. The law of parliamentary privilege applies in Pakistan. It gives members of parliament legal immunity for actions done or statements made in the course of their legislative duties. The idea underpinning this law is that parliamentary business shouldn’t be impeded by restrictions on free speech. In the United Kingdom, where libel laws are the biggest drag on free speech, MPs cannot be censured for defamatory statements made while they are in the Houses of Parliament. Given that blasphemy laws are arguably the most significant restriction on free speech in Pakistan, it would not be unreasonable to expect a similar immunity.

Of course, parliamentary privilege covers lawmakers while they are actually in parliament – and when Rehman was speaking to Dunya TV, she clearly was not in the parliament building. But the fundamental fact remains: the blasphemy reform bill was passing through the legislature and a lawmaker is now facing charges for discussing it. A crucial part of a functioning democracy is the ability to openly and publicly debate significant legislative changes before they are passed into the statute book. If proposed legal changes cannot be openly discussed without politicians facing prosecution, it has serious ramifications for the very functioning of the Pakistani state. It is the public that will suffer if laws and policies can’t be debated and scrutinised.

The blasphemy law has created and facilitated a culture of vigilantism. As soon as someone has been accused of blasphemy, they live under the threat of death. When the young Christian girl Rimsha Masih was falsely accused of blasphemy last year, her family was forced into hiding. According to the Islamabad-based Centre for Security Studies, at least 52 people accused of blasphemy have been killed since 1990. Many die at the hands of angry mobs before they are convicted. Given this high threat of violence, it is perhaps unsurprising that politicians are afraid to touch blasphemy law.

In Pakistan, as in my countries across the world, those who shout the loudest end up wielding the most power. Unfortunately, extremist or conservative elements are more than capable of invoking religion to stir up mass outrage and violence. There is no doubt that this has had a chilling effect on free speech across the board; campaigners working in areas from women’s rights to internet censorship can find themselves dismissed as blasphemers or immoral people, and facing the associated backlash.

Politicians should not be above the law (a particularly sore point given recent corruption allegations), but nor should they be penalised for doing their jobs. A situation where the reform of a particular law cannot be discussed in case the discussion itself breaks that law is worthy of a Kafka story, but not of a healthy and functioning state.