LAWBREAKERS, LAWMAKERS: In some parts of Chicago, violent street gangs and pols quietly trade money and favors for mutual gain. The thugs flourish, the elected officials thrive—and you lose. ... both law enforcement and gang sources say, is that some politicians ignore the gangs’ criminal activities. Some go so far as to protect gangs from the police, tipping them off to impending raids or to surveillance activities—in effect, creating safe havens in their political districts. And often they chafe at backing tough measures to stem gang activities, advocating instead for superficial solutions that may garner good press but have little...