Schools like Binghamton University can’t close their meetings to the public — even if officials deem them “advisory” to the ultimate decision maker.

That’s what New York’s highest court ruled Thursday in a case closely watched by open government advocates.

In accordance with established open-meeting laws, BU already opens gatherings of its University Council, a body which approves student behavior rules, as well as hears about the budget and suggestions to improve the school.

But the ruling has the potential to fling open the doors to dozens of other boards that are deemed “advisory.”

The ruling by the Court of Appeals — New York’s top judicial body — reinstated a trial court’s ruling that had been overturned by a mid-level appellate court about a dispute at the Hostos Community College of the City University of New York that began when Hostos officials barred two CUNY students from entering meetings to address curriculum changes and complain about protests.

The court ruled that although a college might term a group of faculty, staff and administrators “advisory,” the fact that it exercises authority effectively rubberstamped by the actual decision maker means that the open-meetings philosophy should apply.

“While the CUNY Board retains the formal power to veto recommendations of the College Senate, that does not in and of itself negate the Senate’s policy-making role or render the Senate purely advisory,” wrote Chief Judge Judith S. Kaye.

Much of University governance is done by committee at BU, ranging from the academic departments deciding tenure to a committee that suggests alcohol and drug policies.

The decision means that the University cannot designate a committee as “advisory” and close its proceedings to the public.

Kirk McLean, the project coordinator at Binghamton University’s chapter of the New York Public Interest Research Group (NYPIRG), said he hadn’t seen the decision either, but that open meetings are good for civil governance.

“NYPIRG at the statewide level is always fighting for transparent government, and I think all meetings should be open,” he said. “Any decision that upholds our stance must be considered victory.”

Officials at BU and SUNY headquarters in Albany said they couldn’t comment on Thursday’s decision because they haven’t seen it. BU’s lawyer, Barbara Westbrook Scarlett, is out of town until tomorrow. But Katie Ellis, BU’s spokeswoman, noted the University complies with existing open meetings laws.

To determine whether a meeting must be open in accordance with the decision, one must look at the groups’ authority, power model, nature of its role and the power it possesses, said Robert Freeman, the executive director of the Committee on Open Government, an independent state agency that advocates for more open government.

“We don’t have secret ballot voting by members of public bodies in the State of New York,” Freeman said.

The ruling could open meetings to the public in dozens of areas of BU operations, although the implications aren’t yet clear.