How many signatures does the US Supreme Court need to issue a writ of certiorari?

Answer:
At least four of the nine Justices of the Supreme Court must agree to grant a petition for a writ of certiorari. This is called the rule of four. Conversely, five votes are required to determine the outcome of a case after it is heard.
First answer by Marcia1061. Last edit by Marcia1061. Contributor trust: 879 [recommend contributor recommended]. Question popularity: 2 [recommend question].