This paper presents and evaluates Brown’s analysis of the concept of hate speech. His analysis is seen as a valuable contribution to the discussion about the adequate definition of the term hate speech as an ordinary concept, which Brown understands as an equivocal idiom and family resemblance concept. However, as far as the concept of hate speech as a legal term is concerned and especially when the possible impact of Brown’s conception on the legal regulation of hate speech is taken into account it suggests that Brown’s approach appears problematic. Indeed, in the sphere of legal (especially criminal) regu- lation of hate speech the rule of law requires to respect the principle of legal certainty, i.e. to make every effort to define the term hate speech as a legal concept as univocally as possible. This is due to the fact that criminal regulation of hate speech poses potentially a serious threat to freedom of expression as a fundamental right of democratic citizenship.