He left, after a period of "talking people off the walls and off the ledges," preparing to do battle with another New Yorker, Donald Trump -- again.
In the weeks since, Schneiderman -- who led the Trump University fraud lawsuit -- and the nation's other Democratic attorneys general have leapt to the forefront of the anti-Trump resistance, taking on his executive order banning immigration from seven majority Muslim countries.
Washington state Attorney General Bob Ferguson, a Democrat, scored a major victory Thursday night when the 9th Circuit Court of Appeals ruled against reinstating Trump's travel ban. The ruling was made after Ferguson, joined by the attorney general of Minnesota, successfully sued for a halt to the ban, which was granted last week.
"No one is above the law," Ferguson told reporters Thursday night, "not even the President."
It's the first round in what's certain to be a years-long series of battles with the Trump administration over enforcement of labor, environmental and consumer protection rights, as well as health care and immigration laws.
"There's a sense of urgency and a real sense that we are now the guardians of the rule of law in the United States," Schneiderman said in an interview.
"That's the kind of thing that's tough to accept," he said. "But we appear to be confronted by an administration where you question if you take the rule of law seriously."
The attorneys general described to CNN a decision-making process on who would take on Trump based on which offices have budgets large enough to afford to do battle with the Justice Department, and based on which issues resonate most clearly locally.
Schneiderman, in a separate interview, told CNN's Erin Burnett on Wednesday's "OutFront" his legal antagonism toward Trump isn't personal.
"No, not at all. Again, I represent the people of the state of New York and I represent a lot of people who are hurt by this ban," he said. "I represent people who had to make a choice between keeping their jobs and getting back to their families who were separated by this ban ... I have no choice but to go and pursue this."
In the less than two weeks since Trump signed his travel ban, what had been semi-regular conference calls with Democratic attorneys general and, at times, their staffs, have become almost daily.
"We're going to be on the front lines of some of the most important battles for economic and social justice," said Virginia Attorney General Mark Herring.
In the wake of the election, Schneiderman offered guidance to states and counties that want to become "sanctuaries" that do not deport undocumented immigrants who abide by the law.
Noting a spike in hate crimes, he also issued updated guidance immediately after the election to law enforcement agencies on hate crimes.
In Virginia, Herring recently asked state lawmakers for more authority to prosecute hate crimes -- and to broaden the state's definition of hate crimes to more closely match federal law -- because, he said, he fears a less active Civil Rights Division at the Justice Department.
"Given what I heard during the campaign, I'm not optimistic," he said. "It's probably not going to be a very high priority."
"That's an example," Herring said, "of where I have adjusted some of the work that we're doing and trying to make sure that we can keep a president in check if we need to."
Many Democrats' eyes are on Schneiderman -- a dean of sorts among the group, in his second term in one of the nation's largest states -- and California Attorney General Xavier Becerra, who is now just weeks onto the job and is expected to take on a bigger role in the coming months.
Schneiderman's office has bureaus devoted to labor, civil rights and to appeals and opinions. It also has the advantage of being situated in a state where the headquarters -- or major operations -- of a number of major companies.
Should federal agencies -- including the Labor Department and the Environmental Protection Agency, as well as the Consumer Financial Protection Bureau, which liberals fret the Trump administration will gut -- fail to enforce regulations, Schneiderman said his office is prepared to sue to force those rules' enforcement.
"Our office has been not shy about taking on federal agencies about not doing their job," Schneiderman said.
Right after Trump's election, Schneiderman also immediately warned Trump against withdrawing support of President Barack Obama's Clean Power Plan. And he urged New York lawmakers to guarantee free contraception -- a backstop against GOP-led efforts to repeal Obama's Affordable Care Act.
Planning to take on Trump
The strategizing and coordination among the 22 Democratic attorneys general began at a conference in Fort Lauderdale hosted by the Democratic Attorneys General Association.
"It was a moment where we all looked around and realized, this is real," said Hawaii Attorney General Doug Chin. "President Trump being elected is a very real fact, and we need to start thinking about what we're going to do about that. He needs to be aware that as a group, we're going to be incredibly vigilant and assertive."
They already had a model: Republicans during President Barack Obama's tenure.
Greg Abbott of Texas -- now the state's governor who served as its attorney general during most of Obama's administration -- led many of the GOP's legal battles against Obama's immigration orders. And Oklahoma Attorney General Scott Pruitt, Trump's pick for administrator of the Environmental Protection Agency, had regularly sued to block its regulations.
"In some ways, they created -- or maybe I should say they perfected -- a model of going to court and really standing against the presidential administration," said Illinois Attorney General Lisa Madigan.
Democrats had done it before, too. During President George W. Bush's second term, Massachusetts led a group of 12 states and several cities that sued to force the EPA to regulate greenhouse gases.
Travel ban spurs rush to court
The galvanizing moment, the Democratic attorneys general said, was when Trump signed an executive order banning travel to the United States from seven majority Muslim nations.
"As the hours went on, we literally had chaos at the Philadelphia airport," said Josh Shapiro, the newly-elected attorney general of Pennsylvania.
Several states rushed into court to try to block the implementation of Trump's travel ban -- but it was Ferguson who was most successful.
After a judge halted the implementation of Trump's travel ban, the offices of Schneiderman, Shapiro and Massachusetts Attorney General Maura Healey led the drafting of an amicus brief in which 16 additional states backed Washington's case.
The most recent group phone call between the AGs came Tuesday afternoon, when Schneiderman and his staff, as well as the Democratic Attorneys General Association, led a discussion of the travel ban challenge just hours before oral arguments before the 9th Circuit Court of Appeals.
"It was only like 80 years ago that a president's executive order based upon national security authorized citizens of Japanese ancestry, regardless of their backgrounds," Chin said. "It became very important that this was going to be the battle I was going to fight."