[I'm actually going to college after all these years. In an effort to kill two birds with one stone, I'll be posting some of my class assignments here, as well as posting supplementary material inspired by class discussions.]
Arizona Senate Bill 1070 (Wikipedia) implements a number of measures against illegal immigration, including making it a state misdemeanor crime for an alien in Arizona to fail to carry the required documentation, and obliges the police to attempt to determine the immigration status of a person during a "lawful stop, detention or arrest" if there is "reasonable suspicion" that a person is an alien unlawfully present in the United States.
There are a number of larger issues relating to illegal immigration. That illegal immigration is significant social problem seem uncontroversial, but there is considerable disagreement about what component of illegal immigration is the fundamental problem. Are there simply too many foreign nationals in the United States? Are there too many of the wrong sort of foreign nationals, and if so, who precisely constitutes that "wrong sort"? Or is the problem simply that immigration law is is so complicated and unnecessarily exclusive that people whom we might otherwise accept as temporary or permanent residents find it impossible or unacceptably difficult to comply with the law and thus circumvent it, creating subsequent problems? These larger questions are outside the scope of this essay, however; I want to focus instead on the specific problems posed by imposing the obligation on police to determine the immigration status of those they reasonably suspect to be aliens unlawfully present in the United States.
One must charitably assume that if the Arizona legislature is sincere in their stated intentions, they believe that there are too many foreign nationals in the United States, or too many of the "wrong sort", and that federal immigration law, if vigorously enforced, would adequately restrict immigration to the correct numbers and types of people. The question then becomes: does this provision constitute vigorous enforcement of federal law? More importantly, does it constitute only enforcement of federal law? If either answer is negative, then there is ground to doubt both the appropriateness of the provision as well as the motivation of the legislature.
The overall sincerity of the legislature is somewhat supported by other statutes. The legislature has recognized the economic incentive underlying illegal immigration in Arizona with House Bill 2745, the Legal Arizona Workers Act, which mandates that employers verify their employees' immigration status. However, "law-enforcement officials have said that the law includes little budget support for these new obligations" [citation], and the statute does not include criminal penalties for employers hiring illegal immigrants; enforcement is limited to suspension or revocation of offending business's licenses. A law that is not adequately enforced is no law at all.
The provision for reasonable suspicion, however, does not appear to enable vigorous enforcement of immigration law. If this provision were strictly followed, police would discover illegal immigrants in only very narrow circumstances. To be discovered, an illegal immigrant would have to display evidence of other unlawful behavior to justify a "lawful stop, detention or arrest." More importantly, an immigrant would have to display this evidence in a context where documentary evidence relating to his or her immigration status was required by law. In practice, these elements would be present only if an illegal immigrant was operating a motor vehicle in an unlawful manner and did not possess a driver's license. It is as well already at least a violation, and a class 1 misdemeanor if an illegal immigrant were held to be ineligible for a drivers license); if an illegal immigrant were eligible for a drivers license, then failure to possess one while driving would not constitute reasonable suspicion of an immigration violation. This provision therefore adds little additional actual enforcement of immigration law.
The provision for reasonable suspicion also does not appear to constitute only enforcement of immigration laws. Our legal requirements regarding police procedure are typically enforced not by civil or criminal sanctions against individual police officers, but rather by exclusion of evidence during criminal proceedings. Furthermore, exclusion of evidence has "teeth" only when the case a criminal or civil defendant would otherwise be found guilty at trial. While this method of enforcing police procedure might seem counter-intuitive and actively perverse, it has good theoretical and empirical justification.
However, when the adverse effects of a police procedure are never relevant to the introduction of evidence at trial, this method of enforcement becomes entirely inoperative. We cannot merely tell police officers to follow some procedure, we must establish consequences when they fail to do so. When police fail to adhere to correct procedure in ordinary criminal matters, the state might fail to convict someone who would otherwise be convicted; this sanction strikes directly to the motive and purpose of the entire criminal justice process, and gives the police an important incentive to adhere to correct procedure. But what are the sanctions under this provision? Suppose a police officer does not actually have reasonable suspicion that someone might be an illegal immigrant? If the detainee is actually a citizen or legal resident, the officer will not face any individual sanctions. If the person is not a legal resident, they will still be deported. Lacking any way to sanction violations of reasonable suspicion, this provision becomes indistinguishable from the arbitrary decision of the officer.
Worse yet, the provision undermines adherence to standards governing a lawful stop, detention or arrest. If an officer unlawfully detains a person and finds evidence of a crime as a result of that unlawful detention, it is possible and perhaps likely for the detainee to escape the consequences of that crime even though he or she might otherwise have been convicted on the basis of lawfully obtained evidence. However, the reasonable suspicion provision of SB 1070 creates a positive incentive to detain a person — to check their immigration status — while failing to implement a corresponding negative incentive to restrict the officer from unlawfully detaining a person. There is no sanction at all if an officer simply "fails to notice" any evidence of a crime during an otherwise unlawful detention in which the officer only checks the immigration status of the detainee.
We must (at least if we accept the necessity or desirability of the police) give honest and well-intentioned police officers the tools and social permission to do their jobs. But we must also recognize that there are officers who are not entirely honest and well-intentioned. We must take as much or more care to ensure that the latter officers follow correct procedures despite their personal inclinations. The reasonable suspicion provision appears to not only fail to give the well-intentioned officer substantial new tools to enforce the law but also gives bad-intentioned officers the ability to act contrary to correct procedures.
Not only must we reject the specific "reasonable suspicion" provision, we have grounds to call into question the motivation or competence of the Arizona legislature. Even if the legislature is sincerely and legitimately concerned with illegal immigration, this sincere concern might be mixed with illegitimate concerns, especially racial prejudice. We cannot of course definitely conclude that the legislature is motivated by racism — legislative constitutional incompetence is hardly remarkable — but a measure appears to do nothing but give police the ability to harass brown people without fear of sanction raises reasonable suspicions.