nstitution of the United States is the supreme law of the land as
to the matters which it embraces. The constitution of each state is the
supreme law of the state, except so far as it may be controlled by the
constitution of the United States. Every statute in conflict with the
constitution to which it is subordinate is void so far as this conflict
extends. If it concerns only a distinct and separable part of the
statute, that part only is void. Every court before which a statutory
right or defence is asserted has the power to inquire whether the
statute in question is or is not in conflict with the paramount
constitution. This power belongs even to a justice of the peace in
trying a cause. He sits to administer the law, and it is for him to
determine what is the law. Inferior courts commonly decline to hold a
statute unconstitutional, even if there may appear to be substantial
grounds for such a decision. The presumption is always in favour of the
validity of the law, and they generally prefer to leave the
responsibility of declaring it void to the higher courts.

The judges of the state courts are bound by their oath of office to
support the constitution of the United States. They have an equal right
with those of the United States to determine whether or how far it
affects any matter brought in question in any action. So, vice versa,
the judges of the United States courts, if the point comes up on a trial
before them, have the right to determine whether or how far the
constitution of a state invalidates a statute of the state. They,
however, are ordinarily bound to follow the views of the state courts on
such a question. They are not bound by any decision of a state court as
to the effect of the constitution of the United States on a state
statute or any other matter. This judicial power of declaring a statute
void because unconstitutional has been not infrequently exercised, from
the time when the first state constitutions were adopted.

Juries in criminal causes are sometimes made by American statutes or
recognized by American practice as judges of the law as well as the
fact. The better opinion is that this does not make them judges of
whether a law on which the prosecution rests violates the paramount
constitution and is therefore void (_United States_ v. _Callender_,
Wharton's _State Trials_, 688; _State_ v. _Main_, 69 Connecticut
Reports, 123, 128).

If a state court decides a point of constitutional law, set