The punishment for the once-powerful prelate and ex-Archbishop of Washington was announced on Saturday.
A statement by the Holy See says he was: "found guilty of the following crimes perpetrated by cleric: solicitation in Confession and violations of the Sixth Commandment of the Decalogue with minors and adults, with the aggravating circumstance of the abuse of power, therefore he was imposed the penalty of dismissal from the clerical state".
The penalty was confirmed on Wednesday.
"This decision was communicated to Theodore McCarrick on February 15, 2019. The Holy Father recognised the definitive nature of this decision, according to the law, which makes the case resigned, ie not subject to further appeal.
It comes a few days before the Pope is to lead an extraordinary gathering of bishops from around the world over the sex abuse crisis which has eroded the faith of many Catholics and threatened his papacy.
Defrocking means McCarrick, 88, who now lives in a friary in Kansas after he lost his title of cardinal last year, will not be allowed to celebrate Mass or other sacraments.
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