MassLandlords, the nonprofit trade association that represents approximately 2,400 landlords across Greater Boston, is charging that Boston Mayor Michelle Wu’s rent control proposal protects larger, corporate housing operators.

“This rent control proposal could have gone any number of ways, but to us as small landlords, it seems to be the result of developer lobbying,” said Douglas Quattrochi, MassLandlords’ executive director.

He stopped short of outrightly accusing the mayor of cronyism but noted that several members of the committee that helped craft Wu’s proposal were contributors to at least one of her political campaigns.

The trade group’s newly filed lawsuit seeks to force the city to dilvulge documents that show how the members of the mayor’s Rent Stabilization Advisory Committee were selected.

“We actually asked a year ago to find out why MassLandlords and other landlord organizations weren’t invited to the Rent Stabilization Advisory Committee. ... We got rejected in our records request,” Quattrochi said. “But, then once the proposal came out, a whole bunch of warning bells started to go off because we looked at who was on the Rent Stabilization Advisory Committee and, in terms of campaign dollars donated, it's all developers. And you look at who's exempted under the rent control proposal and it's developers.

“So we're trying to find out and we're trying to show if lobbying was at play here in the creation of this rent control proposal,” he said. “It seems like it’s going to benefit developers more than landlords and renters.”

“The public has an interest in knowing what communications passed between [the city of Boston] and who became members of the committee, how the Mayor came to choose those particular individuals, and what motivation may exist for them to persist in advocating for policies know to economists and to the general public to be harmful and contrary to the public interest,” a portion of the legal complaint reads.

Quattrochi noted that MassLandlords, which is based in Cambridge, was not invited to take part in the proposal’s crafting. Less than 5% of MassLandlords’ members reside in Boston. An even smaller portion operate housing within the city.

Wu is seeking to set up a local rent control option for Boston, despite the policy being banned by statewide referendum in 1994. It would require approval from Boston City Council, the state Legislature and the governor to become law.

The mayor’s proposal, now before the City Council, would restrict yearly rent increases to a maximum of 10% in high inflation years and the rate of inflation plus 6% in average years.

Wu’s exemptions include: a 15-year shield for both new and past construction starting from the year the building’s certificate of occupancy was issued, and another for landlords who own six units or less and live on site with their tenants.

Quattrochi said these exemptions leave out a large swath of landlords that could still reasonably be considered small and would be unfairly burdened.

“If [the mayor] had actually talked to us, or invited us to sit on the committee, she would’ve heard immediately that there are so many of our members who live across the street from their properties or in the same neighborhood around the corner from [them], but they’re not in their properties,” he said.

Wu’s proposal also calls for a rent control board or administrator to oversee local rent regulation. Quattrochi said that could create problems for small landlords who may end up needing to ask for permission to make certain improvements to their properties as they did under past rent control regulations while developers enjoy an extended exemption.

Stakeholders across Greater Boston’s development sector are now publicly speaking out against Wu’s effort. The Greater Boston Real Estate launched a $400,000 campaign against rent control this month.

The mayor has dismissed criticism of her proposal, insisting that it is the balanced approach necessary to allow stability for both housing operators and renters.

While appearing on WBUR’s “Radio Boston” earlier this week, Wu expressed confidence that the transparency concerns raised in the lawsuit will be “sorted out,” and said, “many of the special interest groups who might be either listening to fearmongering or practicing fearmongering here really are just trying to stop a policy that that people are scared of.”

“Whether it’s a group that is trying to put a lawsuit forward to just add more news and make sure that there’s as much potential delay in the process as possible, to others who are putting money behind an effort to put a message out there that this is taking us backwards, or assert that City Hall can’t do math or this or that — this is a different proposal that we’re putting forward now compared to what used to exist in Massachusetts and in many places decades ago, or even in some of the cities that are being brought up as examples of what to avoid,” Wu said.

Quattrochi insisted the trade group will see the records request through.

“If there were something in the emails, I think it would just further discredit the mayor’s proposal,” he said. “I think this rent control thing is just some incomprehensible distraction at best, and I'm worried that it’s actually been a lobbying effort of nonprofit and for-profit developers here. ... Whatever we find, we’re going to continue to look into this.”

Last March, the group unsuccessfully attempted to obtain “any and all City of Boston emails to, from, or cc’ing” advisory committee members for the year before Wu announced them, according to the lawsuit filed late last week. The administration, after prodding from the state, only returned a welcome email dated the day after Wu publicly announced advisory committee members and a response stating that invitations to the committee were given through phone calls.

“The implication that in the period March 2021 to March 2022 there were absolutely no email communications between any City department and any of the individuals who went on to become members of the Mayor’s Rent Stabilization Committee struck [MassLandlords] as not credible,” the lawsuit said.

The filing goes on to decry rent control as a policy that will cause “availability discrimination,” a phenomenon where landlords hold properties vacant in order to select tenants with good credit scores and high income.

MassLandlords’ legal complaint also implied a connection between the advisory committee members and contributions to various campaigns for public office. Seventeen of the 25 members put money toward “Massachusetts political races,” the lawsuit alleges.

The group, Quattrochi said, is opposed to rent control in all forms, but would support a “Chapter 40P” program — named for the state law rent control carveout that allows cities and towns to enact rent control and pay landlords the difference between market rent rates and controlled rents.