The city of Pasadena, home of the annual Rose Parade and Rose Bowl college football contest, is violating a new California law aimed at increasing affordable housing, the state attorney general warned Tuesday.

It’s the second such action by Attorney General Rob Bonta after denser housing advocates said more than a dozen communities across California rushed to enact restrictions before the law does not come into force on January 1. More than 150 cities opposed the law as it was envisioned in the Legislature last year.

It allows landlords to build up to four residential units on a single-family lot, a move Bonta says is needed to address the most populous state’s chronic housing and homelessness issues by increasing supply and affordability.

Bonta warned cities to “take seriously their obligations under state housing laws” or “we will hold you accountable.” Bonta staff said his office is evaluating similar orders elsewhere.

Bonta, a Democrat, in November created a new “housing strike forcewithin the state Department of Justice to research violations.

Less than a month before the state law took effect, Pasadena, a Southern California city of about 140,000, passed an ordinance that, among other restrictions, allows authorities to exempting eligible areas by declaring them “historic districts”.

But no such exemption exists under the law, Bonta said.

The ordinance “undermines CS 9 and deprives residents of the opportunity to create badly needed additional housing, under the guise of protecting ‘historic neighborhoods’,” Bonta said in a statement. “It’s disappointing and, more importantly, it violates state law.”

Pasadena’s mayor, city attorney and its director of planning and community development did not immediately comment.

Bonta issued a similar warning to wealthy Silicon Valley last month town of woodside after stating that he was exempt because the whole town is a habitat for endangered cougars. Hours later, city officials said they would finally accept requests for increased housing.

While Bonta told Pasadena officials there is no “signature district” exemption under the state’s housing law, individual properties can be exempt if they are part of a monument, historic property or historic district.

But Bonta said in a letter to Pasadena officials that these designations cannot be arbitrary and must be supported by substantial evidence.

He argued that Pasadena’s criteria, by contrast, are very broad and not tied to historic resources, so they would potentially include large areas of the city.

City leaders also erred in enacting the restrictions as an “emergency ordinance,” Bonta said. He said the city had not provided evidence that the state law would significantly harm public health or safety, let alone required “substantial evidence of significant, quantifiable, direct and inevitable”.

He asked Pasadena to repeal or vary his ordinance to comply with the new state law within 30 days, without saying what might happen if it didn’t.

The law’s author, Senate Speaker Pro Tem Toni Atkins, last month praised Bonta’s efforts to push back on what she called “interesting and creative ways to really fight supportive housing.” .

“These efforts really inhibit and undermine our ability to provide housing for Californians,” she said at a forum hosted by the Sacramento Press Club. She said the goal was “to add soft density in a way that maintains the quality of a neighborhood.”