The crime, any crime is irrelevant. Innocent until proven guilty. If the offense is barrable then I am for the most part in agreement with it. Crossing a border, or THE border, is not a felony, nor is it a violent crime.
Actually illegals (who by definition are criminals, and have already shown a complete disregard to the law simply by being here) are far more likely to commit violent crimes than anyone else, and are almost always guilty of other crimes in addition to being here illegally, like drug dealing, drug possession/use (which is also a NICS dis-qualifier), assault, home invasion, breaking, and entering, identity theft, rape, etc., not to mention retail theft, unlicensed, and reckless driving, tax evasion, and other crimes. I would wager that better than 90% of illegals are guilty of multiple other felonies, many of them violent.
All that is beside the point though, if you are here ILLEGALLY you should have no constitutional protections whatsoever, the constitution is for citizens, legal immigrants, and legal visitors, not ILLEGALS, you come across the border ILLEGALLY you should be taking your chances. One wonders how this case even got to the courts, as soon as he ADMITTED to being an illegal he should have been deported, no hearing, nothing, get on the plane. Clearly he felt no fear of repercussions for openly admitting to being illegal, as it would be politically incorrect to deport him.
If an illegal is caught in this country, as soon as their illegal status becomes known they should be stripped of ALL of their rights (which they never had to begin with), all their property, real, and otherwise seized, and turned over to the state (to compensate for unpaid taxes, increased welfare, insurance costs, and crime rate, etc.), and imprisoned for the maximum term for there crimes, including being here illegally, hard labor, then as soon as they have completed there sentences be deported to SOUTHERN Mexico (in the case of Mexican illegals). Additionally whoever hired them if it can be shown knowingly hired an illegal, should be charged with criminal conspiracy, aiding, and abetting, and as an assessory in any crimes the illegal committed, as well as RICO, and enterprise corruption, and additional fines, and jail time for hiring them in the first place.