do all members of the jury have to agree
Hung jury Juries in criminal cases are generally, as a rule, required to reach a unanimous verdict, and juries in civil cases typically have to reach a majority on some level. If a defendant has been found guilty of a capital offense, one that could result in the death penalty if the person is eligible, the opinion of the jury must be unanimous if the defendant is to be sentenced to death. Currently, two states, Oregon and Louisiana, do not require unanimous verdicts in criminal cases. Each requires a 10-2 majority for conviction, except for capital crimes: Oregon requires at least 10 votes out of 12 for felonies, but unanimity for first degree murder, and Louisiana requires all 12.
Sixth Amendment to the United States Constitution Originally, the Supreme Court held that the Sixth Amendment right to a jury trial indicated a right to "a trial by jury as understood and applied at common law, and includes all the essential elements as they were recognized in this country and England when the Constitution was adopted."[4] Therefore, it was held that juries had to be composed of twelve persons and that verdicts had to be unanimous, as was customary in England.