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Legal Moments In History

The leap year and the law

· 5 minute read

· 5 minute read

Leap years — years with an extra day at the end of February — were invented as a way to keep calendar years (which are normally 365 days long) and astronomical years (which are 365.2425 days long) in sync with one another. That means leap years occur every four years on years that are divisible by 4.

That rule is subject to a minor exception: leap years do not occur if the year is divisible by 100 (i.e. 1800, 1900, etc). Of course, most of us remember that 2000 was a leap year, which brings up yet another exception: if the year is divisible by 400 (i.e. 1600, 2000), then it is a leap year.

And if you’ve noticed today’s date as being February 29, you’ll know that 2020 is a leap year.

With deadlines and timelines being so important in the area of law, one can’t help but wonder what kind of implications leap years have therein. Perhaps the most obvious consequences are found in contractual computations, and in determining statutes of limitations and criminal sentencing.

However, considering that the existence of the leap year predates the U.S. Declaration of Independence, February 29 doesn’t really cause too much legal trouble.

For statute of limitations and criminal sentencing calculations, February 29 is counted as a separate day when a length of time is statutorily specified in terms of days.

On the other hand, when a length of time is specified in years, the day essentially disappears, and a leap year is considered a common year for purposes of the statute.

In spite of the issue seeming settled, it still comes up quite a bit in court.

Take Habibi v. Holder, a case decided on December 8, 2011.

Jawid Habibi was convicted of Battery of a Current or Former Significant Other, a misdemeanor under California law. Habibi received a 365-day sentence to be served through the year 2000, which was a leap year.

The Department of Homeland Security subsequently tried to deport Habibi, claiming that his California conviction made him removable under 8 U.S.C. § 1227, since his conviction was of a “crime of violence…for which the term of imprisonment [is] at least one year.”

So, to recap, the state sentence was 365 days, but the federal statute required imprisonment for at least one year – and the court’s job was to determine whether 365 days equaled one year under the statute.

The confusion resulted in the case reaching the level of the federal appeals court to decide that 365 days is, in fact, one year.

Another criminal case in which leap years were relevant for measuring the passage of time is 2015’s People v. Phillips, in which the trial court shorted the defendant two custody credits against his sentence, failing to take into account that 2008 and 2012 were leap years. The appeals court corrected this error.

Instead of timelines and calendars, how are “leapers” — those born on February 29 — affected legally by their unique situation?

Specifically, does a leaper turn 18 or 21 on February 28 or March 1?

Some states, but not all, have statutes that explicitly express which date is to be used.  Nevertheless, one can make the determination for any state by simply looking at its common law.

Namely, if a state excludes the day of birth in age computation, March 1 is the date the leaper turns 18 or 21. If a state includes the day, then February 28 is the date (check out this American Law Reports article for a state-by-state list).

So, as silly as it may sometimes seem, legal disputes over leap years and leap days come up even today.  With 2016 being a leap year, it’s probably a good idea to keep this issue in mind.

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