Born in the early 1800s, Mahune was a member of the lesser strata of Hawaiian nobility, subordinate to the high chiefs or aliʻi.

[4][2] Considered Hawaii's Magna Carta, it laid down the inalienable rights of the people, the principles of equality of between the makaʻāinana (commoner) and the aliʻi (chiefs) and the role of the government and law in the kingdom.

Hawaiian historian Jon Kamakawiwoʻole Osorio believe that it was American missionary William Richards, who was mainly responsible and that Mahune and Jonah Kapena, were only assistants to the creation of the Declaration of Rights.

Serving as a judge in Lahaina for a period of time, he returned to Honolulu in 1846, where he went back to working for the government as a civil servant.

He died without writing a will; his landholdings had been quite extensive including properties in each of the main islands showing his rank and favor in the royal court.