Giving the opinion of the court, Chief Justice Waite said: "We think it may be safely said that State legislation which seeks to impose a direct burden upon inter-state commerce, or to interfere directly with its freedom does encroach upon the exclusive power of Congress. The statute now under consideration in our opinion occupies that position." "Inaction by Congress," the court held, "is equivalent to a declaration that interstate commerce shall remain free and untrammelled." This meant that the carrier was "at liberty to adopt such reasonable rules and regulations for the disposition of passengers upon his boat, while pursuing her voyage within Louisiana or without, as seemed to him best for the interest of all concerned. The statute under which this suit is brought, as construed by the State court, seeks to take away from him that power so long as he is within Louisiana, and while recognizing to the fullest extent the principle which sustains a statute unless its unconstitutionality is clearly established, we think this statute to the extent that it requires those engaged in the transportation of passengers among the several States to carry colored persons in Louisiana in the same cabin with whites is unconstitutional and void. If the public good requires such legislation it must come from Congress and not from the States." Justice Waite here expressed his fear as to the delicate ground on which he was treading in saying: "The line which separates the powers of the States from this exclusive power of Congress is not always distinctly marked, and oftentimes it is not easy to determine on which side a particular case belongs. Judges not infrequently differ in their reasons for a decision in which they concur. Under such circumstances it would be a useless task to undertake to fix an arbitrary rule by which the line must in all cases be located. It is far better to leave a matter of such delicacy to be settled in each case upon a view of the particular rights involved." Thus the way was left clear to vary the principle of interpretation according to the color of the citizens whose rights might be involved. In view of the subsequent decisions in separate car cases, moreover, the following portion of Justice Waite's opinion as to a clause in the law involved in the case of _Hall_ v. _DeCuir_ is unusually interesting. "It does not act," said he, "upon the business through the local instruments to be employed after coming within the State, from without or goes out from within. While it purports only to control the carrier when engaged within the State it must necessarily influence his conduct to some extent in the management of his business throughout his entire voyage. We confine our decision to the statute in its effect upon foreign and interstate commerce, expressing no opinion as to its validity in any other respect."[28]