Weeks before the Massachusetts Bay Transportation Authority hikes fares across the system by an average of 9.3 percent, lawmakers Thursday moved to limit such increases in the future.
State senators approved a state budget amendment that would cap transit system fare increases to less than 5 percent every two years — a limit that some believed they had already enacted.
State Senator Sonia Chang-Diaz, a Democrat from Boston, said she proposed the amendment because she worried about T fares rising at an unsustainable rate.
“The T and transit, in general, are a public good, and when you offer communities and individuals the access to affordable and sustainable transportation, you’re offering them the ability to improve their lives,” she said.
But she also put forth the idea, she said, because senators thought they had already set the policy a couple of years ago.
Thursday’s debate should have felt like déjà vu: In 2013, the Senate discussed the same 5 percent proposal — and appeared to come to a consensus about it — as politicians wrangled with a sweeping transportation bill. But when the bill ultimately passed, the language had been changed to allow the MBTA to increase fares up to 10 percent every two years instead.
After the MBTA began considering fare hikes last year that could surpass 9 percent, state senators cried foul, arguing that their intent had been to limit increases to 5 percent.
The MBTA and the state transportation department, however, insisted they were following state law when the fiscal control board voted to increase prices system-wide by 9.3 percent: The law in question says the MBTA “shall not increase fares at intervals of less than 24 months or at an annual rate greater than 5 percent.”
As the MBTA and its fiscal control board debated fare hikes late last year, senators who pushed for the 5 percent proposal in 2013 and transit activists hammered the board and the administration for hiking fares too high.
Thursday’s amendment would not affect the increases scheduled to start in July.
Chang-Diaz called the measure debated Thursday a “clarification” for the law. But it was a characterization that State Senator Bruce E. Tarr, the minority leader, pushed back against. The amendment was a “substantive change” from existing law, he said.
Tarr eventually approved of the measure, which passed by a 34-5 margin and with support from four Republican senators.
Viriato M. deMacedo, one of the five senators who voted against the measure, said he worried that lowering the cap could take away a tool from the fiscal control board that was created to improve the agency. Its efforts were already making a difference, he said.
“This is a slippery slope,” said deMacedo, a Plymouth Republican. “I understand we want to control the costs, but we also want to give [the fiscal control board] tools to fix this problem in that five-year window.”
State senator John F. Keenan, a Quincy Democrat who voted against the amendment, said he believes the MBTA needs more flexibility to help provide better service.
“There’s just a whole host of structural physical needs on the Red Line in the area that I represent, and I think we have to find a way to pay for them so that service is predictable,” he said.
Officials at the MBTA declined to comment.
Jacquelyn Goddard, a spokeswoman for the Massachusetts Department of Transportation, said the existing law already places “reasonable limits” on the fares.
“While fare hikes are a last resort, the MBTA believes modest increases for some transit users are appropriate as other steps to increase revenue are taken,” she wrote in an e-mail.
Board members have taken some steps to ensure the fare hikes protect more vulnerable riders, such as voting to postpone any further increases until 2019, and lowering some fares while hiking others.
The change to the fare hike limit still faces several hurdles: It would need to gain support from a House-Senate conference committee, as well as Governor Charlie Baker.
The governor’s office deferred comment to the state transportation department Thursday, but past proposals from the administration suggest he might not be a fan of such an amendment. When Baker first proposed legislation to overhaul the MBTA, he tried to eliminate the fare hike cap altogether.
That move discouraged transit activists who said a fare cap was essential, particularly for students, seniors, and low-income customers. They said the limits existed to ensure modest, predictable increases after the T failed to do that for its customers on its own.
In 2012, the MBTA raised fares by an average of 23 percent after keeping them flat for 5½ years. The anger over the sudden, steep hike led legislators to push for the 2013 limit.
Thursday’s vote was lauded by transit activists who believed the fare hike limit should have been at 5 percent all along. Charlie Ticotsky, policy director at Transportation for Massachusetts, said the amendment cancels out any ambiguity about future hikes.
“It protects all riders, but especially those who do not have a choice to take different modes, who may not own a vehicle, or don’t have a driver’s license or can’t afford any other modes of transportation,” he said.
Activists also cheered that the amendment makes clear that the limits apply to the T’s monthly passes, not just its single-ride fares. Transportation Secretary Stephanie Pollack has said passes are not legally fares, but discounts, and are not bound by the fare increase cap.
Monica G. Tibbits-Nutt, a member of the fiscal control board, said she believes that gaining more clarity about predictable fare hikes would be better for riders.
“I would obviously love more revenue for projects, state of good repair,” she said. “But we will work with whatever framework they give to us.”