Daylight Saving Time: A Historical Legal Overview

The practice of setting the clock forward by one hour during the day to increase daylight hours in the evening and reduce them in the morning is known as Daylight Saving Time (DST). While DST has been used in the US and many European countries since World War I, it was first established as a standard by the Uniform Time Act of 1966, which was signed into law by President Lyndon B. Johnson. The Act allowed states to opt-out of DST and some did, including Arizona and Hawaii. While DST has been the subject of debate and proposed changes over the years, as of 2024, federal law still prohibits states from enacting permanent DST.

The Uniform Time Act of 1966

Prior to the Act, each state had its own scheme for when daylight saving time (DST) would begin and end, and in some cases, which parts of the state should use it. The law, as originally written, required states that observe DST to begin it at 2 a.m. local time on the last Sunday in April and to end it at 2 a.m. local time on the last Sunday in October. It also explicitly preempted all state laws related to daylight saving time.

The Act has been amended several times. In 1972, it was amended to allow states with more than one time zone to exempt one time zone from DST, in addition to exempting the whole state. In 1986, it was amended again to move the uniform start date for DST to the first Sunday in April. The latest amendment, as part of the Energy Policy Act of 2005, extends DST by four or five weeks, with DST beginning on the second Sunday in March and ending on the first Sunday in November.

The Sunshine Protection Act

The main purpose of the Act is to establish permanent DST in the United States, eliminating the need to change clocks twice a year. Currently, under the Uniform Time Act of 1966, most states observe DST, with clocks "springing forward" by one hour in March and "falling back" by one hour in November. However, this practice has faced increasing opposition in recent years, with many Americans viewing it as an unnecessary and disruptive tradition.

However, the Act has also faced opposition, particularly from those who argue that permanent DST would result in darker mornings and disrupt daily routines, especially for students who would have to commute to school in the dark during winter months. There are also concerns about the potential health impacts of disrupting the body's circadian rhythm, with groups like the American Academy of Sleep Medicine advocating for permanent standard time instead.

Despite these debates, the Sunshine Protection Act has gained significant support. In 2022, it passed unanimously in the Senate but failed to advance in the House of Representatives. As of 2024, the bill remains stalled, with no recent movement towards bringing it to a vote. Meanwhile, several states have passed their own legislation to adopt permanent DST if federal approval is granted, and others continue to consider similar proposals.

World War I and II

During World War I, Germany began observing daylight saving time on May 1, 1916, as a way of conserving fuel. The rest of Europe soon followed suit. The practice was not adopted in the United States until March 19, 1918, when the Standard Time Act was passed. The law was implemented to conserve fuel needed for war industries and extend the working day.

The 1918 Standard Time Act was only meant to be in effect for seven months of the year and was discontinued nationally after World War I ended. However, individual states continued to adjust their clocks ahead one hour in spring and back one hour in fall.

When World War II began, the need to conserve resources resurfaced, and in 1942, the U.S. Congress once again passed legislation implementing daylight saving time. This time, the law imposed daylight saving time for the entire nation for the entire year and was called "War Time". It was instituted by President Franklin Roosevelt on February 9, 1942, and remained in effect until September 30, 1945, when World War II ended.

After World War II, there was no federal law on daylight saving time until 1966, and localities could choose when to begin and end it or do away with it entirely. This led to a patchwork of different daylight saving policies across the country.

Federal law

The Uniform Time Act of 1966 established a uniform set of rules for states opting to observe daylight saving time. The act mandated standard time within the established time zones and provided for advanced time, with clocks to be advanced one hour beginning at 2:00 a.m. on the last Sunday in April and turned back one hour at 2:00 a.m. on the last Sunday in October. States were allowed to exempt themselves from daylight saving time as long as the entire state did so.

In 1973, Congress enacted a trial period of year-round daylight saving time in response to the 1973 oil embargo by the Organization of Arab Petroleum Exporting Countries (OAPEC). The trial was hotly debated, with supporters pointing to increased daylight hours in the summer evenings, and opponents concerned about children travelling to school in the dark. After several traffic accidents involving schoolchildren in Florida, the year-round law was repealed.

In 2022, the United States Senate passed the Sunshine Protection Act, which would have permanently activated daylight saving time. However, it did not become law as it was not approved by the U.S. House of Representatives. As of 2024, federal law still prohibits states from enacting permanent daylight saving time.

In 2023, the Sunshine Protection Act was reintroduced, but as of April 2024, there has been no progress on the bill.

State-level policy changes

Several states have considered legislation about daylight saving time in 2024, but only Oklahoma has actually passed legislation. In other states, legislation has either failed to pass or been stuck in committee.

In Oklahoma, Senate Bill 1200 was approved by both chambers of the state legislature and then signed into law by the governor. Under the bill, Oklahoma would switch to permanent daylight saving time as soon as such a policy is allowed under federal law.

In other states, various laws have been proposed, and some states even have competing legislation. Examples of proposed policy changes include:

• Enacting permanent standard time
• Enacting permanent daylight saving time contingent upon a change in federal law that permits such a policy
• Enacting a clock change contingent upon a similar policy being adopted by neighboring states
• Creating a statewide referendum about daylight saving time
• Commissioning a study to examine the impacts of permanent standard time or daylight saving time

While only Oklahoma’s law has been passed this year, a number of states have already changed their laws in prior years.

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