Does the ex post facto prohibition preclude a state from charging a defendant with a newly defined capital crime under a retroactivity provision

QUESTION PRESENTED The ex post facto prohibition in Article I, section 10, of the United States Constitution prevents a change in law from being applied retroactively when it aggravates a crime, increases the possible punishment for an offense, or alters the quantum of evidence to impose that punishment. Does the ex post facto prohibition preclude a state from charging a defendant with a newly defined capital crime under a retroactivity provision when, after the acts alleged, the legislature altered the facts that must be proved beyond a reasonable doubt by adding a new fact that the jury must find to establish the offense and removing a different fact that the jury must find to return a death sentence?