National Mutual Insurance Company of District of Columbia v…
“ It is elementary that the exclusive responsibility of Congress for the welfare of the District includes both power and duty to provide its inhabitants and citizens with courts adequate to adjudge not only controversies among themselves but also their claims against, as well as suits brought by, citizens of the various states. It long has been held that Congress may clothe District of Columbia courts not only with the jurisdiction and powers of federal courts in the several states but with such authority as a state may confer on her courts. ”
