Blue Laws

Blue laws are regulations that attempt to restrict activities or the sale of specific goods or services for religious reasons. The most common in the United States is the restriction of selling alcohol on Sundays in some municipalities.

Rumor has it that the laws were originally printed on blue paper, but that’s been debunked over the years. The Wikipedia page presents this at the etymology of the phrase.

the word blue was used in the 17th century as a disparaging reference to rigid moral codes and to those who observed them, particularly in blue-stocking, a reference to Oliver Cromwell’s supporters in the parliament of 1653.

While many blue laws have been overturned, some have been retained and even upheld by the courts. Common arguments are they they contribute to the stability of society, and they contribute to the free exercise of religion