You are in fact and in finding reading the law incorrectly.
8 U.S. Code § 1325 - Improper entry by alien
(b)Improper time or place; civil penalties Any alien who is apprehended while entering (or attempting to enter) the United States at a time or place other than as designated by immigration officers shall be subject to a civil penalty of—
(1)
at least $50 and not more than $250 for each such entry (or attempted entry); or
(2)
twice the amount specified in paragraph (1) in the case of an alien who has been previously subject to a civil penalty under this subsection.
Civil penalties under this subsection are in addition to, and not in lieu of, any criminal or other civil penalties that may be imposed.
but unless their papers are falsified, they have not committed anything other than a violation of 1325, which is punishable by a nice hefty $50 - $250 fine. You can see what constitutes an actual immigration related crime under 18 US Code Chapter 69, conveniently linked here for your reference: https://www.law.cornell.edu/uscode/text/18/part-I/chapter-69 note also that none of the provisions of 8 USC 1325 provide for deportation proceedings as a remedy.
Instead the US Government is attempting to use antiterrorism provisions 18 USC 1226a, which still require that you place a “suspected alien” in either removal proceedings or charge them with an actual crime within 7 days of detention or the government must release the alien
anyway, I realize I am climbing up a greased flagpole here. tl;dr version: the media has spread a narrative that these are ‘criminal aliens’ when there is in fact no such thing and Congress has repeatedly refused to codify such a thing into law.