the.com/law of the land

means The established legal rules that apply to everyone within a country or territory, binding regardless of personal consent.

from A phrase traceable to Magna Carta (1215), which promised judgment only 'by the law of the land' — legem terrae in the original Latin — meaning the established legal custom of the realm, not the arbitrary will of a ruler. The phrase stuck because it did real work: it drew a line between lawful authority and raw power, and later legal systems, including American constitutional law, borrowed it almost unchanged to mean the body of law currently in force and binding on all.