Manhattan District Attorney Cyrus Vance Jr.’s office was prepared to bring state criminal charges against former Trump presidential campaign manager Paul Manafort, according to media reports that surfaced Friday. But any case brought by state prosecutors under New York law would have to clear a big hurdle—the prohibition on double jeopardy.

Manafort is scheduled to be sentenced in two separate federal cases next month. He was found guilty on eight financial fraud related counts by a federal jury in Virginia last August. He subsequently pleaded guilty to separate charges in Washington, D.C., in September.