Ex parte Royall is a United States Supreme Court case that dealt with the issue of whether a state court could constitutionally deny a defendant the right to a jury trial in a criminal case. The case involved a man named William Royall, who was charged with the crime of larceny in the state of Virginia. Royall argued that the Virginia court had denied him his right to a jury trial, as guaranteed by the Sixth Amendment of the United States Constitution. The Supreme Court held that the Virginia court had indeed violated Royall's right to a jury trial. The Court reasoned that the Sixth Amendment guarantees the right to a jury trial in all criminal cases, and that the Virginia court had no authority to deny Royall this right. The Court further held that the Virginia court's decision was unconstitutional and that Royall should be granted a jury trial. In conclusion, the Supreme Court held that the Virginia court had violated Royall's right to a jury trial, as guaranteed by the Sixth Amendment of the United States Constitution. The Court ordered that Royall be granted a jury trial and that the Virginia court's decision be overturned.

In Ex Parte Royall, the Supreme Court was tasked with determining whether a Virginia statute that excluded African Americans from serving on juries violated the Fourteenth Amendment. The majority opinion held that it did not violate the amendment because there were other protections in place for African Americans and their rights to serve on juries had already been established by state law. However, Justice Harlan dissented from this opinion and argued that excluding any group of people based solely on race or color is unconstitutional under both federal and state laws. He further argued that allowing such discrimination would undermine public confidence in jury trials as well as lead to unequal protection under the law for all citizens regardless of race or color. Ultimately, he concluded that denying African Americans an opportunity to participate in jury service was a violation of their constitutional rights guaranteed by both federal and state laws.