Illegal Immigrants at Hazleton's Gates

Today a federal judge in Pennsylvania began to hear the case for and against a Hazleton ordinance that threatens to fine landlords who rent to illegal immigrants and revoke the permits of businesses that employ them. Enforcement of the law, which is similar to measures proposed in many other municipalities, has been blocked pending the outcome of the case. The ACLU argues that the law violates the Constitution's Supremacy Clause by impinging on the federal government's authority to enforce the immigration laws; the right to due process by failing to provide adequate means to contest the city's determination that a particular tenant or employee is in the country illegally; and the right to equal protection by encouraging discrimination against Latinos. The city (my mother's hometown, incidentally) argues that illegal immigrants are bad news, committing crimes and driving up the costs of education and health care. I'm not sure how those concerns, whether or not they're justified, rebut the ACLU's constitutional arguments.