The Middletown Road stop on the 6 line in the Bronx reopened after $27 million in renovations.
The MTA replaced stairs, roofs, lights and signs.
One thing it didn't do: Make the station accessible to the disabled.
"We need an accessible city and this is something that the mayor's office and the city council don’t really pay attention to," said Dustin Jones with the Center for the Independence of the Disabled.
On Tuesday, the U.S. Justice Department joined a lawsuit filed by disability rights advocates against the MTA.
It charges the authority violated the Americans with Disabilities Act by failing overhauling the station without studying whether it was feasible to install an elevator to make it accessible.
Acting Manhattan U.S. Attorney Geoffrey Bermman said in a statement: "There is no justification for public entities to ignore the requirements of the ADA 28 years after its passage."
Jones is a plaintiff in the original lawsuit. He says the Justice Department's action has big implications for a system where barely a quarter of the 493 stations are fully accessible.
"It shows that everything that we are doing is not going on deaf ears," Jones said.
The MTA determined it was not feasible to install an elevator at the Middletown Road station — but federal transit officials found the MTA's study lacking. Still, the MTA completed the renovation. The federal government later determined that an elevator could have been added.
The MTA declined to comment beyond saying it is: "committed to adding and maintaining accessibility for the century-old subway system."
The MTA has long said it does not have enough money to quickly make all stations accessible. But last month, the MTA's new point man for the subways, vowed to re-examine the issue.
"Don't just assume it has to be an elevator," said Andy Byford, President of New York City Transit. "Let's look with a fresh pair of eyes, an innovative pair of eyes, at how we can make better use of scarce tax dollars to come up with an accessible solution."
The MTA plans to spend $1 billion by 2019 to make more stations compliant with the Americans with Disabilities Act. However, it is only enough money to upgrade 19 stations. Advocates say Tuesday's legal action sends a strong signal to the MTA.
"This means the MTA will think twice with future station renovations and make sure that accessibility improvements are essential to renovations moving forward," said accessible transit advocate Colin Wright, with the Transit Center.