Maybe nothing. If a party to the decision appeals, the lower court could get overturned. Also, if in a subsequent case a party relies on the lower court decision, a court could choose not to follow it or a higher court could overturn it.
If the supreme court makes a ruling, lower courts are obliged to follow it. Any judge who fails to do so can find his rulings overturned. Basically, that means the losing side can go to another judge, point out that the first judge's decision contradicts the supreme court, and ask to have that decision set aside.
One of the most important factors in a judicial system is consistency - laws need to be applied in the same way everywhere they are applied.
the elements of a decision of the U.S. Supreme Court must be followed by the lower courts.
the elements of a decision of the U.S. Supreme Court must be followed by the lower courts.
What was the effect of the Supreme Court's decision in Loving v. Virginia
majority opinion
By issuing a judicial review.
Judicial Review
Dissent
no one knows
Dissent
Dissent
Dissent
Dissent