TORONTO -- Ontario Education Minister Liz Sandals appointed an outside expert Tuesday to conduct a review of the troubled Toronto District School Board, where she said "a culture of fear" exists among staff.

Police were called to a recent meeting of Canada's largest school board amid accusations one trustee held the director of education hostage in her office in the latest example of headline-grabbing infighting.

"It is now clear that we have no choice but to act," said Sandals.

The TDSB was the subject of two external audits which uncovered problems with capital and structural deficits and with trustee expenses, but it's the public disputes between staff and trustees that drew the government's attention.

"The school board has been plagued by issues that go beyond purely financial concerns, with almost daily examples of confrontation, obfuscation and a lack of communication," said Sandals.

The chair of the TDSB had asked the government to intervene after a tense standoff between education director Donna Quan and several trustees over her refusal to release her employment contract. TDSB staff have complained of intimidation by some trustees.

"When the top of the organization is consumed by what appears to be internal warfare some days, when you reach that state, if you don't step in as a government you can end up with that disharmony eventually affecting the students," said Sandals.

It's not just the current staff and trustees at the TDSB that have led to the problems, added the education minister.

Sandals said she's been observing the TDSB for a couple of decades and has seen the relationship and the function of the board becoming progressively more dysfunctional and acrimonious.

"And that's why we feel at this point we need to step in," she said. "It is clear that the issues at TDSB go beyond competing personalities."

The New Democrats wondered why an external review was needed when, by law, staff at the TDSB are required to report directly to elected trustees, but for some reason apparently feel they don't have to do that.

"This is causing great difficulties in terms of people being able to hold this board to account," said NDP education critic Peter Tabuns. "My hope is this review will look at this question of who do the administrators at the board report to if they're not reporting to the people who are elected to oversee them."

Sandals named Margaret Wilson, the former Register of the Ontario College of Teachers, to conduct the external review, which will include an examination of operational issues and focus on the TDSB's governance structure.

Appointing a provincial supervisor to take over operations of the board would be "a last resort," but the option remains on the table, warned Sandals.

"While we are not placing the board under supervision at this time, there is nothing I am announcing today that precludes that step at some point in the future," she said.

The Progressive Conservatives questioned whether Wilson's review would result in any real changes, and said Sandals should have appointed a supervisor to run the TDSB.

"To begin with, they have more power and the ability to straighten things up immediately," said PC education critic Garfield Dunlop.

The problems at the board are putting public confidence at risk, and not just in Toronto, but across the province, warned Sandals.

"With 246,000 students in nearly 600 schools, public confidence in the TDSB is critical to ensuring public confidence in the entire education system," she said.

"I know if we don't step in and get the board focusing where the board should focus, which is on the success and well-being of students, we are going to have a problem very, very soon."

Full statement from TDSB director