THE LATE Supervisor Charles McGlashan called it "The Adams Amendment," a 2008 political agreement reached to help the Sonoma-Marin Area Rail Transit tax get passed.

The title has stuck and its namesake, Supervisor Susan Adams, is fighting to make sure that the promise is not forgotten.

In 2008, after weeks of wrangling between leaders of SMART and the Transportation Authority of Marin, the rail agency promised it would not compete with the transportation authority for state and federal funds.

At the time, I thought that was a promise that would be difficult, if not impossible, to keep.

Today, Adams is trying to keep Marin's countywide transportation agency from abandoning the deal, one that helped keep her from actively opposing the SMART sales tax when it was on the 2008 ballot in Marin and Sonoma counties.

She didn't support the commuter rail tax, but she stayed out of the campaign.

Adams, a Transportation Authority of Marin commissioner, was worried that SMART's quarter-cent sales tax would fall far short of paying for the promised 69-mile passenger train and bike and pedestrian path. She pushed the "Adams Amendment" because she was worried that TAM and SMART would become rivals for North Bay transportation money.

If SMART and TAM agreed not to fight over the same pots of money, she was more comfortable with Measure Q, which passed after three previous train taxes had failed.

Rather than competing, TAM is now poised to make SMART one of its priorities for future grants. That's money that Adams and other critics of the move claim should be going to fix local streets and roads and for local transit buses.

At an April 28 TAM meeting, Adams tried to derail the move, but lost on a 9-4 vote. Many of the TAM commissioners involved in that vote weren't party to that 2008 agreement.

"I think there's going to be an issue of public trust and accountability," Adams warned.

"In transportation, nothing is forever," cautioned Supervisor Steve Kinsey, TAM's chairman who was in those 2008 meetings.

Given a historic recession and state and federal cutbacks in transportation projects, the political landscape has changed dramatically in less than three years. The composition of commissions change. The rules and regional priorities for funding have shifted.

Marin also is getting political pressure from Sonoma. Its countywide transportation agency is helping out SMART and it wants Marin to do its fair share.

TAM, in its draft 25-year list of transportation improvements, is asking for federal money for a SMART station near Fireman's Fund in Novato, to extend the train from San Rafael to Larkspur Landing and for $29 million to help it close SMART's $88 million shortfall.

At the April meeting, steadfast train opponent Mike Arnold said TAM's proposed grant priorities add up to a "bail out" of SMART.

Among those backing the SMART funding were commissioners representing Novato Kinsey, Supervisor Judy Arnold and Novato Councilwoman Carole Dillon-Knutson who know that TAM's support is key to getting the Fireman's Fund SMART station back in the train plan.

Another was Commissioner Al Boro, who serves on both the TAM and SMART boards. He said the train will prove critical to Marin's future a way to get up and down Highway 101 without driving a car.

Adams says her amendment is being derailed. Others might call it collaboration.