Easley v. Kellom et al. was a United States Supreme Court case that dealt with the issue of whether a state court had the authority to issue a writ of habeas corpus to a prisoner held in federal custody. The case arose when a prisoner, William Easley, was arrested by federal officers in the District of Columbia and held in federal custody. Easley then filed a petition for a writ of habeas corpus in the Supreme Court of the District of Columbia, seeking to be released from federal custody. The Supreme Court of the District of Columbia granted the writ, and the federal officers appealed the decision to the Supreme Court of the United States. The Supreme Court of the United States held that the Supreme Court of the District of Columbia did not have the authority to issue a writ of habeas corpus to a prisoner held in federal custody. The Court reasoned that the writ of habeas corpus was a judicial power, and that the federal government had exclusive jurisdiction over matters involving federal prisoners. The Court also noted that the writ of habeas corpus was a fundamental right, and that the federal government had the exclusive power to protect and enforce that right. In conclusion, the Supreme Court of the United States held that the Supreme Court of the District of Columbia did not have the authority to issue a writ of habeas corpus to a prisoner held in federal custody. The Court reasoned that the writ of habeas corpus was a judicial power, and that the federal government had exclusive jurisdiction over matters involving federal prisoners. The Court also noted that the writ of habeas corpus was a fundamental right, and that the federal government had the exclusive power to protect and enforce that right.

In Easley v. Kellom et al., the Supreme Court was asked to decide whether a state court had jurisdiction over an action brought by a citizen of another state against citizens of the same state in which the suit was filed. The majority opinion held that such suits were not within the scope of federal judicial power, and thus could be heard by a state court. However, Justice Field dissented from this ruling on two grounds: first, he argued that under Article III Section 2 of the Constitution, Congress has exclusive authority to determine when cases involving citizens from different states can be tried in federal courts; second, he maintained that since there is no express grant or denial of jurisdiction for such cases in either statute or constitutional law, it should remain with Congress alone to make any determination as to their proper disposition. In conclusion then Justice Field concluded that while it may have been reasonable for states to assume some limited powers over these types of disputes prior to 1871 (when this case arose), they do not possess any inherent right or authority beyond what has been granted them by Congress itself.