On Monday afternoon the Chicago Police Department provided details on how exactly the city’s new gun law will work. This was kind of important since the law went into effect earlier in the day.

What impact—if any—the law will have on crime and violence in Chicago is being discussed and debated around the country, though it wasn’t discussed or debated in the Chicago City Council before aldermen passed it 45-0 a few days ago.

Meanwhile, the police department still can’t or won’t say how often the city’s old gun ordinance—the one this is replacing since the Supreme Court came down against it two weeks ago—was actually enforced.