原来是美国殖民时期的清教徒所订的法律，禁止在星期天跳舞、喝酒等，以后转用为有关个人行为的严格规定，如禁止公务员涉足酒家、舞厅、夜总会、或不该接受款宴等等：

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A blue law， thus called because it was supposedly written on blue paper when first enacted by Puritan（清教徒） colonies in the 17th century， prohibits selling of certain types of merchandise， or retail or business activity of any kind， on certain days of the week （usually Sunday？）。 In Texas， for example， blue laws prohibited selling housewares such as pots， pans， and washing machines on Sunday， until 1985. Many southern states prohibit selling alcohol on Sunday.

（There is no actual evidence for the printing of these laws on blue paper； Connecticut is widely believed to have done so， but the surviving documents are on the same paper as other state laws， and there is no contemporary mention of blue paper. Nonetheless， the name is short and clear， and unlikely to change.）

Likely， all blue law stems from the first such statute set down by the Emperor Constantine 1300 years before the Puritans：

"Let all judges and all city people and all tradesmen rest upon the venerable day of the sun. But let those dwelling in the country freely and with full liberty attend to the culture of their fields； since it frequently happens that no other day is so fit for the sowing of grain， or the planting of vines； hence， the favorable time should not be allowed to pass， lest the provisions of heaven be lost." —— Given the seventh of March， Crispus and Constantine being consuls， each for the second time. A.D. 321.

Many unusual features of American culture——such as the fact that one can buy groceries， office supplies， and housewares from a "drug store"——are the result of blue laws （drug stores were allowed to remain open to accommodate emergency medical needs）。

blue sky laws 蓝天法

指美国各州对投资公司、经营公司的债券买卖进行监督和保护投资者免遭欺诈的《公司证券欺诈防治法》之俗称。

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Introduction

While the SEC（Scurities and Exchange Commission：证券交易委员会）directly， and through its oversight of the NASD（美国证券交易商协会） and the various Exchanges， is the main enforcer of the nation's securities laws， each individual state has its own securities laws and rules. These state rules are known as "Blue Sky Laws".

The origin of the term is a bit unclear， but the first use of the term that we are aware of is in an opinion of Justice McKenna of the United States Supreme Court， in 1917. Justice McKenna wrote the Court's opinion in Hall vs. Geiger-Jones Co.， 242 U.S. 539 （1917）， which was three cases， all dealing with the constitutionality of state securities regulations. Justice McKenna wrote

The name that is given to the law indicates the evil at which it is aimed， that is， to use the language of a cited case， "speculative schemes which have no more basis than so many feet of 'blue sky'"； or， as stated by counsel in another case， "to stop the sale of stock in fly-by-night concerns， visionary oil wells， distant gold mines and other like fraudulent exploitations." Even if the descriptions be regarded as rhetorical（带修辞色彩的）， the existence of evil is indicated， and a belief of its detriment； and we shall not pause to do more than state that the prevention of deception is within the competency of government and that the appreciation of the consequences of it is not open for our review.

Unfortunately， Justice McKenna never gave a reference to the "cited case" that he referred to， and the Hall cases have become known as The Blue Sky Cases， and Justice McKenna as the author of the phrase.

While these laws vary from state to state， the laws require registration of securities offerings， and registration of brokers and brokerage firms. Each state has a regulatory agency which administers the law， typically known as the state Securities Commissioner. A list of state securities commissioners， and their addresses， is available in our Guide to State Securities Regulators.

While anti-fraud regulations are most commonly enforced by the SEC and the various SROs， the states also have the power and authority to bring actions against securities violators pursuant to state law. Each state has its own securities act， known colloquially as the "blue sky law"， which regulates both the offer and sale of securities as well as the registration and reporting requirements for broker-dealers and individual stock brokers doing business （both directly and indirectly） in the state， as well as investment advisers seeking to offer their investment advisory services in the state.

Recently， federal legislation was enacted which limited the ability of the states to review， limit or otherwise restrict the sale of most securities. The legislation was designed to eliminate the duplicitative nature of the federal and state securities laws. Today， in most instances， the states authority to review registration of securities offerings that are offered on a national basis have been severely restricted. However， there are notice and filing requirements in each state， which must still be complied with. Additionally， the legislation did not affect the ability of the state regulators to conduct investigations and to bring fraud actions.