A state may not impose a charge for the enjoyment of a right granted by the federal constitution… The power to impose a license tax on the exercise of these freedoms is indeed as potent as the power of censorship which this Court has repeatedly struck down… a person cannot be compelled ‘to purchase, through a license fee or a license tax, the privilege freely granted by the constitution.’
— MURDOCK V. PENNSYLVANIA 319 US 105 (1942)