Explain where they get the authority to pass laws dealing with crimes other than those enumerated in the Constitution.
That would be the Necessary and Proper Clause
"can any thing be more absurd, more arrogant, or more pernicious to the peace of Society, than for self created bodies, forming themselves into permanent Censors, and under the shade of Night in a conclave, resolving that acts of Congress which have undergone the most deliberate, and solemn discussion by the Representatives of the people, chosen for the express purpose, and bringing with them from the different parts of the Union the sense of their Constituents, endeavouring as far as the nature of the thing will admit, to form that will into Laws for the government of the whole; I say, under these circumstances, for a self created, permanent body, (for no one denies the right of the people to meet occasionally, to petition for, or to remonstrate against, any Act of the Legislature &ca) to declare that this act is unconstitutional, and that act is pregnant of mischief; and that all who vote contrary to their dogmas are actuated by selfish motives, or under foreign influence; nay in plain terms are traiters to their Country, is such a stretch of arrogant presumption as is not to be reconciled with laudable motives: especially when we see the same set of men endeavouring to destroy all confidence in the Administration, by arraigning all its acts, without knowing on what ground, or with what information it proceeds and this without regard to decency or truth."
-- George Washington; from letter to Burges Ball (Sept. 25, 1794)