Regulating parties by constitutional rules in liberal democracies

When establishing constitutional rules that regulate political parties, liberal democracies struggle between civil liberties - thus tolerating anti-democratic parties - and potential threats of democratic breakdown, which can be reduced by prosecuting and prohibiting anti-democratic parties. We suggest that liberal democracies must balance false positives and false negatives by combining ex ante and ex post regulatory mechanisms. By making use of a unique dataset of thirty-seven liberal democracies collected by the authors, we find empirical results consistent with our positive theory. An extensive review of the normative debate and case law provides additional qualitative support.