Screen shot 2013-10-16 at 9.11.57 AMAs expected, charter schools were an early and significant point of disagreement between Democrat Bill de Blasio and Republican Joe Lhota during the first of three televised mayoral debates Tuesday evening.

The candidates share starkly different visions for the role of charter schools in the city’s school system. But their dispute on Tuesday night also hinged on a new issue — whether de Blasio had “flip-flopped” on the issue, a charge that he batted away as a page “out of the Republican playbook.”

Early on in the televised debate, de Blasio was asked to explain his plan for the city’s charter sector, which includes 183 schools and 70,000 students — about 6 percent of the public school student population. The public advocate has been under fire from charter school advocates in recent weeks for saying he’d charge rent to some of the schools in city-owned buildings.

De Blasio has so far offered vague details about which schools he would charge rent and how much each would pay. He has said he would use a “sliding scale” based on how much private money the schools have been able to raise to make those decisions.

De Blasio responded first by talking about his plan to raise taxes on New Yorkers earning more than $500,000 to fund universal prekindergarten, which he said would serve the city’s entire school system, not just the charter sector. He then offered something of an olive branch to the sector — with conditions.

“I’ve said I’ll work with the charters that are doing a good job, that are including every child,” said de Blasio, alluding to criticism that charters serve high-need students at lower rates than district schools. “[T]hose that aren’t doing such a good job, that aren’t inclusive, I’ll be tougher on them. I won’t favor them the way the Bloomberg administration did.”

De Blasio and his campaign didn’t elaborate on how he’d enforce student enrollment in charter schools. Beginning this year, charter school authorizers are required by law to consider school enrollment and admission data in charter renewal decisions.

Some advocates in the charter sector welcomed the comments, while others criticized them.

James Merriman, CEO of the New York City Charter School Center, said was “pleased” to hear that de Blasio wants to work with the charter sector. But Bill Phillips, who runs Northeast Charter School network, another advocacy group, said he was less optimistic.

“[I]t should scare people when a city official says he will unilaterally go beyond a state law to impose rules only on schools he doesn’t like,” Phillips said. “What happens when he decides not to like your school?”

De Blasio also said he’d leave alone schools with lower resources, which he called “non-profit charters,” an inaccurate suggestion that most of the city’s other charter schools are affiliated with for-profit organizations. Though for-profit charter schools are common around the country, charter schools in New York are prohibited under state law from partnering with for-profit management organizations. Just seven city charter schools are affiliated with for-profit groups after being grandfathered in under the 2010 law, and all are housed in private space.

De Blasio said he’d seek rent money from charter schools that are able to afford it.

“The ones that have millions of dollars of surplus, that have lots of private assets at their disposal, why shouldn’t they pay some rent to help us out so we can run the best school system possible?” de Blasio said.

The comments sounded like a change to his opponent, Lhota, who has embraced charter schools from the start.

“Mr. de Blasio has changed his mind and has flip-flopped on this issue,” Lhota said. “During the entire Democratic primary, he said he was going to make sure that are charged rent. Only now we get this nuanced difference.”

De Blasio has long hinted that he sees a difference between wealthier charter school networks and those that operate on shoestring budgets. In January, he called out the CEO of Success Academy Charter Schools, saying at a forum, “There is no way in hell that Eva Moskowitz should get free rent, okay.” He repeated that criticism throughout the primary and clarified his proposal in recent months, with fact-checkers at the New York Times noting that he specifically “broached the topic as early as July.”

Lhota has tried to capitalize on his differences with de Blasio on charter schools and he seized on the opportunity again in the debate.

“The reason why charter schools shouldn’t pay rent is because they are public schools and we don’t charge our public schools rent, whether they are a charter school or a regular public school,” Lhota said.

De Blasio, who holds a 40-point lead in the latest polls, reprised a familiar attack on Lhota in response to the charge that his own position had changed.

“This is right out of the Republican playbook,” de Blasio said. “Mr. Lhota is distorting the facts.”