New regulations are coming for home-sharing businesses operating in D.C. Mayor Muriel Bowser — who has been semi-opposed to the measures — will let them become law, but she will decline to add her signature. Bowser said that a bill passed by the D.C. Council that applies to platforms like Airbnb, VRBO and HomeAway is too restrictive and possibly unconstitutional.

In a letter sent Tuesday to Council Chair Phil Mendelson, Bowser said the bill that passed in November — which allows homeowners to use the platforms to rent out a bedroom or basement for short periods of time, but prohibits such rentals in second homes — would rein in too severely what has become a popular practice in the city.

“While I understand that some community members have concerns about the impact of short-term rentals on their neighborhoods, I also know that many homeowners use short-term rental platforms to help make mortgage payments and remain in the District,” she wrote. “I believe the Council could have struck a better balance between these legitimate interests.”

This appears to be only the second time that Bowser has let a bill become law without her signature. The mayor also registered her opposition to the city’s landmark paid family leave legislation, which passed with a veto-proof margin, without signing it.

Bowser also told Mendelson that Attorney General Karl Racine — whose office has cracked down on illegal commercial home-sharing operators — believes a provision of the law requiring that the platforms turn data over to the city may be unconstitutional. Earlier this month, a judge in New York City preliminarily sided with Airbnb and HomeAway in their claim that a new law requiring extensive data-sharing violated the Fourth Amendment of the U.S. Constitution prohibiting unreasonable searches and seizures.

A Balance Between Competing Interests?

The debate over what to do about home-sharing in D.C. started in early 2017 and stretched over 18 months, with opposing sides arguing passionately that short-term rentals either help democratize the tourism industry and allow residents to earn extra income from spare space in their homes or further exacerbated the city’s affordable housing crisis by encouraging residents and commercial operators to use apartments and houses for short-term visitors instead of long-term tenants.

Proponents of the bill unanimously approved by the Council say a proper balance was struck. Residents will still be able to use the platforms to rent out bedrooms and basements in their primary homes for short periods of time as much as they want, provided they are present at the time of the rental. If they are not present, an annual 90-day cap will apply, unless they are granted a hardship exemption because their job or family situation requires them to travel outside of D.C. for long stretches of time. Most notably, the bill prohibits anyone who owns a second or third home from using it for short-term rentals.

Home-sharing fans, the platforms themselves and Bowser say the bill is too restrictive, and in her letter to Mendelson, the mayor says it is “more restrictive on short-term rentals than some surrounding jurisdictions.” That is true — to a certain extent. Arlington County allows short-term rentals in a primary residence, but only requires the owner to live there for 185 days each year. However, it also bans the use of second homes for short-term rentals. The same is true in Montgomery County, although the cap for short-term rentals when an owner is not present is 120 days a year.

Cost concerns

Bowser also said she was concerned with the estimated cost of the Council’s bill — $104 million in lost tax revenue over the next four years. D.C. Chief Financial Officer Jeffrey DeWitt told the Council last year that under the city’s current zoning code, short-term rentals in many residential neighborhoods are already illegal, though they still happen. As such, if the Council’s bill took effect and enforcement ramped up, he estimated that between 80 and 90 percent of all existing short-term rentals would be declared illegal, costing the city a large chunk of tax revenue it currently collects from platforms.

But Mendelson has asked the D.C. Zoning Commission to consider amending the zoning code to allow short-term rentals, and last year it started moving in that direction, requesting that the city’s Office of Planning offer guidance on what changes should be made. Provided the zoning code is changed, Mendelson says the bill’s overall cost will come down significantly.

The bill isn’t law yet, though. Now that Bowser has returned it to the Council unsigned, it heads to Congress for the usual 30-day review all pieces of legislation get. Provided it makes it through that, it’s not expected to take effect until Oct. 1 of this year.

This story originally appeared on WAMU.