402 HASTINGS—POLICE POWER OF THE STATE.  [June19, 
So the state comes to have the right and, when an emergency 
arises, to be under the duty to take action that affects foreign and 
interstate commerce; and, on the other hand, regulations of 
foreign and interstate commerce which pass inside of state boun- 
daries must always affect persons and things that are supposed to be 
under state control, and alter the rights of the states with respect 
to them. 
In both the License cases and in the Passenger cases, only Chief 
Justice Taney and Justice Woodbury seem to have recognized that 
the two powers must, to a certain extent, interlace and cover the 
same field ; that the only way to harmonize them is to find them, 
to a certain degree, concurrent, and leave that of Congress para- 
mount. The other judges seem still to imagine that they may be 
wholly separated. Such a view seems yet to prevail. 
The passage in Cooley’s Constitutional Limitations discussing the 
possibility of conflict with national authority growing out of the 
plenary police power of the state seems to countenance such a 
view: 
1** Any accurate statement of the theory upon which the police power 
rests will render it apparent that a proper exercise of it by the state can- 
not come in conflict with the provisions of the constitution of the 
United States. If the power extend only to a just regulation of rights 
with a view to the due protection and enjoyment of all, and does not 
deprive any of that which is justly and properly his own, it is obvious 
that its possession by the state and its exercise for the regulation of the 
property and actions of its citizens cannot well constitute an invasion 
of national jurisdiction, or afford a basis for an appeal to the protection 
of the national authorities.” 
This passage has remained practically unchanged in all the editions 
of Judge Cooley’s work since its first publication in 1868. 
If this means, as on its face it seems to, that the police power of 
the states, rightly conceived, is the same under the federal consti- 
tution that it would be without that constitution, and so no conflict 
is possible except under a misconception of the one or the other, 
then lawyers and judges, not excepting Judge Cooley, who have 
appealed so often to that instrument to avoid attempts to exercise 
that power, against which they could cite nothing but the constitu- 
tion, have been strangely blind to the true theory. 
If we are to ? ‘‘ follow the real truth of things rather than an 
1 Cooley’s Con. Lim., 5th ed., p. 708; Ist-ed., 1868, p. 574. 
2 Machiavelli, Le Prince, Fr. Tr., chap. xv. 
