754, to review the affirmance of a judgment, 43 F. The Acts of Augand Augdo not require a result different from that here reached.

In a suit in the federal district court against a state officer charged with the administration and enforcement of the Louisiana Unemployment Compensation Law, brought by plaintiffs engaged in navigation and operation of vessels used in improving navigable waters of the State, and praying a declaratory judgment that the state law, as applied to them and their employees, is unconstitutional, it was the duty of the court to withhold such relief, it appearing that, under the state law, a taxpayer who pays a challenged tax to the appropriate state officer may maintain a suit for reimbursement. When asked to enjoin an unconstitutional state tax, it is their duty to withhold relief when state law with the right of appeal to this Court affords adequate protection. It is in the public interest that federal courts of equity should exercise their discretionary power to grant or withhold relief so as to avoid needless obstruction of the domestic policy of the States, and Where federal courts, in the exercise of their jurisdiction to render declaratory judgments, are called on to adjudicate what are essentially equitable causes of action, they are free upon equitable grounds to grant or withhold the relief prayed, and considerations which have led federal courts of equity to refuse to enjoin the collection of state taxes, save in exceptional cases, require a like restraint in the use of the declaratory judgment procedure. In the light of its opinion, findings, and conclusions of law, the District Court's dismissal of the suit rests wholly upon its declaration that, as applied to the plaintiffs, the state statute is constitutional, and its judgment is, in effect, a declaratory judgment.

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