What was the most important US Supreme Court decision in the 20th and 21st centu

Question:

What was the most important US Supreme Court decision in the 20th and 21st century?

Please, anything except Roe vs. Wade and Brown vs. Board of Ed. I'm tired of seeing these two cases all the time. Thanks

Additional Details

4 days ago
Dude thanks for your answer , which you just cut and pasted from google. Anyways, I just want 20th cases, or more recent cases in this century.

Best Answer - Chosen by Asker: 4 days ago
Dude thanks for your answer , which you just cut and pasted from google. Anyways, I just want 20th cases, or more recent cases in this century.