U.S. Supreme Court Justice Anthony Kennedy announced Wednesday he plans to retire, giving President Donald Trump a coveted opportunity to replace him with a more conservative judge.

For years, the 81-year-old Kennedy has been the decisive vote on many significant cases.

His replacement could fundamentally change the makeup of the court, as a Trump appointee would probably create a solid five-member conservative majority.

WATCH: Explainer on Supreme Court Justices
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