A sense of humor helps. Some who take part have signed on to the "World Superhero Registry," an online outfit where a member must be one "who does good deeds or fights crime while in costume."
But like other historical flash points, when the public becomes personally involved in crime fighting, vigilantism becomes a threat, experts say, especially if government appears powerless.
"When you go broke, be creative. Outsource criminal justice back to the people," says Peter Scharf, a criminologist at Tulane University in New Orleans. "When you go through a very chaotic period with crime, people are going to become more innovative."
Hard numbers on the rise in amateur crime fighters don't exist, but policing experts say the trend is noticeable. At the National Sheriffs Association (NSA), which runs some 26,000 Neighborhood Watch groups, activity has risen to nearly the levels of the winter of 2001, following 9/11.
NSA crime prevention specialist Robbie Woodson links the uptick directly to the Congressional decision in 2007 to cut community policing grants by 68 percent, much of which had been aimed at low-level crime in transitional neighborhoods. Ms. Woodson says President Obama's inaugural call for "a new era of responsibility" took direct aim at what she sees as a widening gap – both perceived and real – between criminal activity and the ability of police to control it.