The 2002 film, "The Gangs of New York," provides a bloody vision of new immigrant groups clashing with native citizens on Manhattan island in the 1800s. While many immigrants today continue to be vilified or reviled by politicians and media pundits, their presence actually makes a neighborhood better. Increases in immigration reduce the crime rate, according to the research of University of Colorado sociologist Tim Wadsworth published in June's issue of Social Science Quarterly. "It really flies in the face of every argument you hear around immigration," he tells Boulder's Daily Camera . "When you look at what's going on in Arizona now or California 10 years ago, one of the main arguments for restricting immigration is the supposed increase in crime." Analyzing data from censuses in 1990 and 2000, as well as FBI crime reports, Wadsworth investigated some 450 American cities with populations larger than 50,000, and compared legal and illegal immigration stats with crime figures. "Immigration explains between 10 and 20 percent of the drop in crime," he says. "It's statistically significant. It's not the big-bang explanation for the entire decrease, but it's among the top five factors." Meanwhile, national immigration reform is no longer just an issue for liberal politicians like Boulder Congressman Jared Polis . In the shadow of Arizona's strict new law, some evangelical Christian leaders are voicing support for a bill in Congress, according to Mshale , though some major groups, like Focus on the Family in Colorado Springs, are undecided. As for Arizona's new immigration law, Scott W. Houghton, a Denver police officer, writes that his peers in the Southwest have been somewhat maligned in characterizations. He writes in a guest opinion to The Denver Post : "Most officers in Colorado and Arizona are not jack-booted Nazi thugs just looking for a way to harass the citizenry. We use the legal tools available to us to do our jobs."