Felix Frankfurter

“ There is no difference between declaratory suits involving an equitable remedy and other equity suits. Where an actual controversy with federal jurisdiction exists over the legal relations of adverse parties, discretion usually cannot properly be exercised by refusing an adjudication. ”

“ It requires no elaboration to convince me that the threat is a real and substantial interference by allegedly illegal governmental action. As that threat has taken a definite form by the enforced agreement for withdrawal, we have not something that may happen but a concrete written notice requiring withdrawal by this respondent from the System on the happening of a fact which is contrary to the Board's idea of the public interest. Whether the Board's idea of a legitimate public interest is correct is the very point at issue. ”