A blue law is one restricting activities or sales of goods on Sunday, to accommodate the Christian sabbath. The first blue law in the American colonies was enacted in Virginia in 1617. It required church attendance and authorized the militia to force colonists to attend church services.
Contrary to popular belief, there is no evidence to support the assertion that the blue laws were originally printed on blue paper. Instead, the word blue was commonly used in the eighteenth century as a disparaging reference to rigid moral codes and those who observed them (e.g., "bluenoses").
Other early blue laws prohibited work, travel, recreation, and activities such as cooking, shaving, cutting hair, wearing either lace or precious metals, sweeping, making beds, kissing, and engaging in sexual intercourse. The Puritans believed that a child was born on the same day of the week on which it was conceived. Therefore, the parents of children born on a Sunday were punished for violating the blue law nine months earlier.
Blue laws have operated to protect Christian business owners from competition on their sabbath. However, they don’t protect those (such as Jews and Muslims) whose sabbath is Saturday from competition on their sabbath. Thus blue laws have established a double standard in favor of Christians.
Although blue laws requiring Sunday church attendance disappeared in the nineteenth century because they violated citizen’ rights to religious freedoms, other blue laws have continued to exist into the modern era. In Texas, for example, blue laws prohibited selling house wares such as pots, pans, and washing machines on Sunday until 1985, and car dealerships in the state continue to operate under blue-law prohibitions. Many states still prohibit selling alcohol on Sunday, although it’s now the second busiest shopping day of the week.
In 1985, the Supreme Court of Canada ruled that the Lord's Day Act of 1906 was an unconstitutional violation of The Canadian Charter of Rights and Freedoms It found that there was no true secular basis for the legislation and its only purpose was, in effect, to establish a state religious-based requirement, and was therefore invalid.
Similarly, courts in New York and Connecticut have ruled that, because blue laws were created and propagated by religious groups for religious purposes, they are unconstitutional.