By Operation Of Law

What does By Operation Of Law mean in American Law?

The definition of By Operation Of Law in the law of the United States, as defined by the lexicographer Arthur Leff in his legal dictionary is:

Automatically, so to speak, and not through a contractual or other purposeful juridical act of a person. If, for example, a statute were passed providing that all leasehold interests longer than ninety-nine years were to become fees, then one would be vested with fee title “by operation of law.”