If you were to conjure up an image of offensive advertising in the subway, you might think of the anti-Muslim ad campaign that the MTA fought so fiercely to keep off of its train platforms and out of its cars.

That experience led the MTA board to vote to ban all political advertising in the transit system earlier this year.

But that same policy that was meant to tamp down on religious intolerance is now being used against something as politically correct as the living wage movement. 

The MTA is taking down 1,000 ads for the Amalgamated Bank that read: “Raising the minimum wage lifts up all New Yorkers. Join the bank that fights for working families.”

The ads were supposed to have run through next week. But when they came to the attention of MTA executive Jeffrey Rosen, he whipped off a memo to Outfront Media, the transit agency's advertising contractor.

"This advertisement...should not have been approved by Outfront Media," Rosen wrote, "and now remedial steps must be undertaken to revise or remove them."

It's just the latest in a string of incidents that have shown how tricky it is to ferret out political speech in a vast multi-billion-dollar enterprise — and stay on the right side of the Constitution.  

Amalgamated's president, Keith Mestrich, said he was "shocked" when he learned his company's ad campaign — for which he said the bank paid "six figures" — was being taken down.

"This is a crazy policy that the MTA has," he said. "It is a real restriction on free speech in this country."

Mestrich said Amalgamated, which is the largest union-owned financial institution in the country, had raised the minimum wage for its own employees to $15 an hour earlier this year, and so felt like the ad campaign was "the right thing to do."

(New York Gov. Andrew Cuomo also supports raising the minimum wage, which could potentially make this a sticky situation for the leadership of the MTA, which is a state agency. The governor's office has not yet responded to requests for comment.)

But Amalgamated is not the only group to recently run afoul of the MTA's new policy. The transit agency earlier this month removed ads from the Freelancers Union that address issues of wage theft.

"Funny how corporations are people when it comes to politics," the Freelancers Union ad read, "but faceless machines when it comes to PAYING actual people." 

A judge earlier this month ruled the MTA couldn't ban ads for the humorous documentary "The Muslims are Coming!" (That film was produced by "Vaguely Qualified Productions.")

In her decision, U.S. District Judge Colleen McMahon wrote that she could not conclude were "political on their face." She said the called the MTA's refusal to run the ads "arbitrary" and "untethered to any articulated or articulable standard.”  

The judge also cited ads from the cable television show "Mr. Robot," which read "CORPORATIONS OWN YOUR MINDS" and "BANKS OWN YOUR MONEY," calling them "blatantly political."

The MTA's Lisberg said the agency's ad company, Outfront, would be more vigilant.