law unto oneself

Meanings

1. One who is free from the constraints of law or rules.
2. One who flouts the law or conventional wisdom; one who ignores rules or logic to behave according to his or her own standards.
3. One who is lawful in the absence of an enforced law; one who behaves with integrity.

Etymology

Probably from Romans 2:14 in the King James Version of the Bible (see the quotation under sense 3 below), though the term has come to have the opposite meaning, as senses 1 and 2 indicate. Sense 3 is now largely limited to references to the Bible verse.