‘Paedophile hunters’ have attracted global media attention. The limited literature on paedophile hunters, which documents their emergence in contemporary liberal democracies, pays scant attention to how their use of intrusive investigative methods may threaten the procedural rights of suspects and undermine the integrity of the criminal justice system. This article fills this normative ‘gap’ in the literature. It draws upon media coverage, criminal procedure jurisprudence, and criminological scholarship to analyse the regulation of paedophile hunting in English and Welsh law. The article suggests that domestic law does not afford adequate protection to due process and the fundamental human rights of those falling under the paedophile hunter's purview. Unless paedophile hunting is constrained by a narrower and more robustly enforced regulatory regime, it should not be permitted, let alone encouraged, in contemporary liberal democracies.