Rahm Emanuel’s interest in marijuana seemed to come out of nowhere. In truth, it was months in the making.

These arrests burden local courts, resulting in punishments meted out so capriciously that armed dealers are sometimes let off with little more than a slap on the wrist while casual users are locked up for possessing a dime bag. And though about 90 percent of these arrests are effectively thrown out in court, they cost county taxpayers at least $78 million and tens of thousands of police hours a year.

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To everyone’s surprise, in strode Danny Solis, one of the mayor’s most loyal supporters. And he didn’t just show up: he announced plans to introduce his own proposal to the City Council to turn low-level pot possession into a ticketable offense. While the proposal still gave police the option of making arrests, it noted that “a disproportionate number of these arrests are of minorities” and proposed “a conversation among experts in health and public safety fields to gather data and information.” Twenty-six other aldermen signed on as cosponsors.

What’s undeniable, though, is that the issue belonged to the mayor from that point on.

By the first of June shootings citywide were up 11 percent and murders 46 percent over 2011. Meanwhile, police superintendent Garry McCarthy was insisting to a group of downtown business leaders that the city’s public safety problem was a matter of “perception” since overall crime totals were still going down.

That was the spirit of the June 21 council hearing where, for more than three hours, aldermen fretted about the plan. They worried about sending the wrong message to children, declared their firm opposition to drug dealing and gangbanging, and emphasized—then emphasized a few more times—that they’re not advocates of smoking or legalizing reefer . . . even if it’s funny to joke about.

“How much would 15 grams of marijuana cost?” wondered 27th Ward alderman Walter Burnett Jr.