But the quote within the footnote also includes this statement: "[A]lthough illegal aliens’ presence in the country is no crime, their entry into the country is." I hope Federale will, drawing upon his expertise, weigh in on its accuracy.
In my (admittedly amateur) view, the statement is wrong, based upon my sampling of the Montana U.S. Attorney's press releases over several years. That office routinely prosecutes cases of illegal re-entry by illegal aliens apprehended in the state. And obtains convictions (although a guilty plea is typically involved).
(Illegal re-entry transpires if one enters without inspection [i.e. illegally] after having been previously removed [i.e. "deported"]. And it's a felony: See 8 USC 1325a and 1326, the distinction between the two having always escaped me. Perhaps Federale could also clarify this.)
Most of these illegal re-entry cases in Montana involve Mexicans. Since Mexico doesn't abut Montana, it's clear that the authorities needn’t catch someone in the act of violating the international border in order to convict them of illegal entry.
But could the presence after illegal entry or re-entry still, in some sense, be "legal"? Probably not. Consider the case of Angelo Cristobal-Sarmientos [press release], who — in the federal district court in Great Falls on March 5, 2014 — was sentenced to 13 months and 1 day incarceration for illegal re-entry. Here's a quote from that press release:
Cristobal-Sarimentos advised that he was a citizen of Mexico and in the United States illegally. There is no record that Cristobal-Sarimentos ever applied for or obtained the permission of the United States Attorney General or his successor the Secretary of the Department of Homeland Security to reenter the United States. Moreover, records indicate that Cristobal-Sarimentos had previously been deported subsequent to a felony conviction. [Emphasis added.]The press release about the sentencing, earlier in 2014, for illegal re-entry of Juan Sanchez-Gonzalez employed the similar language "in the country illegally."
Then again, the criminal penalties called out in 8 USC 1325a and in 1326 are specifically for illegal entry and re-entry. Neither section says anything about being here illegally. And perhaps this is significant, since it's true that people who become illegal aliens by overstaying a visa haven't committed a criminal offense in so doing. (Although I don't have a source on that, it's widely known.)
Over to Federale for further explanation!