Charter school authorizers in Minnesota whose schools fall in the lowest 25 percent of public schools could be required to close those schools or submit an explanation to the state.

That’s if state Senate Bill 836 passes. Charter school supporters are split over whether the legislation from state Sen. Terri Bonoff would strengthen or weaken charter schools in the state where the movement began.

Increased regulation is unnecessary and could threaten the independence that’s core to charter schools’ identity, said Eugene Piccolo, executive director at the Minnesota Association of Charter Schools, and Kara Kerwin, president of the Center for Education Reform.