Lopez-Valenzuela, et al. v. Maricopa County, et al.

In April 2008, the American Civil Liberties Union challenged the Arizona anti-immigrant law Proposition 100 in federal court claiming it violated the U.S. Constitution by unjustly denying a select group of people a fair legal process. In December of 2008, a federal court denied in part a motion to dismiss the suit filed by the defendants, and in allowing the case to proceed, the court also certified a plaintiff class. The parties filed cross-motions for summary judgment after extensive fact discovery on the remaining claims in the case. On March 29, 2011, the district court denied the plaintiffs’ summary judgment motion and granted summary judgment for defendants. In June of 2013 the U.S. Court of Appeals for the Ninth Circuit upheld the district court’s order in a 2 to 1 decision.

The ACLU sought review of that 2-1 ruling by the en banc court, and the case was reargued before an 11- judge panel in March, 2014. The ACLU argued that the voter-approved law unfairly singles out immigrants as a flight risk, ignoring their ties to the community and the complete lack of any evidence that immigrants are more likely to flee than other people. The law thus deprives these immigrants of their constitutional right to due process and violates the principle that people are presumed innocent until proven guilty.

On October 15, 2014, in a 9-2 decision, the en banc U.S. Court of Appeals for the Ninth Circuit struck down Proposition 100. Writing for the majority, Judge Raymond Fisher wrote, "Proposition 100 categorically denies bail or other pretrial release and thus requires pretrial detention for every undocumented immigrant charged with any of a broad range of felonies, regardless of the seriousness of the offense or the individual circumstances of the arrestee, including the arrestee's strong ties to and deep roots in the community.” Judge Fisher continued, “The defendants maintain that this unusual, sweeping pretrial detention statute, directed solely at undocumented immigrants, comports with substantive due process. It does not. The Supreme Court has made clear that "[i]n our society liberty is the norm, and detention prior to trial or without trial is the carefully limited exception.”

Arizona attempted to have Ninth Circuit's ruling challenged at the Supreme Court, but the Supreme Court declined to hear the case.