One of the most difficult areas in church–state law involves the conflict between freedom of speech and freedom of religion. In the United States, at least at the level of basic principle, that conflict has been largely resolved for decades. Ever since Cantwell v. Connecticut, we have accepted that people don't have a right to be free from criticism—or even offense—directed at their religious beliefs. Speakers may criticize religion, ridicule religious doctrines, and even confront believers directly, so long as they respect ordinary time, place, and manner restrictions and do not incite imminent violence.

In other words, in American constitutional law, freedom of speech generally trumps claims that religious sensibilities have been wounded. The First Amendment does not contain a right not to be insulted.

The situation in Europe is more complicated.

The European Court of Human Rights holds that states have a legitimate interest in protecting believers from gratuitous disrespect directed at their religious beliefs. As far back as the Otto-Preminger-Institut case, the ECtHR has indicated that freedom of expression does not include a right to insult religious beliefs in ways that undermine social peace or the rights of others. This concern applies to both majority and minority religions. The underlying idea is not that religion is immune from criticism, but that the state may regulate expression that crosses the line from criticism into deliberate and unnecessary insult.

Europe today is experiencing deep disagreements about religion's role in public life. What counts as legitimate critique to one audience may register as degrading or contemptuous to another. As a result, courts in Europe, including the ECtHR, are increasingly asked to draw difficult lines between  public debate and pointless provocation.

I recently discussed this issue, among others, with Judge Ioannis Ktistakis of the ECtHR on a new episode of the Legal Spirits podcast. Towards the end of the episode, Judge Ktistakis identified this tension—balancing the right of believers to have respect shown to them and their beliefs against the competing right of free expression—as one of the major challenges facing the ECtHR today.

Readers interested in comparative church–state law may find the conversation illuminating, not only for what it reveals about the ECtHR's approach, but for what it tells us about the assumptions Americans often take for granted when thinking about free speech and religious freedom.