Fairfax County’s school board will decide Thursday night whether principals should be allowed to install surveillance cameras in high school cafeterias and other indoor spaces on campus.

The measure has the unanimous support of high school principals and appears likely to pass. Six board members indicated strong support for the policy change at a work session last month.

Others expressed reservations about invading students’ privacy, and Dan Storck (Mount Vernon) and Sandy Evans (Mason) questioned whether parents have had a fair chance to learn about the proposal and weigh in.

The plan was presented in September by principals who argued that cameras would have helped catch the culprits responsible for a rash of food fights last year. More recently, camera advocates have emphasized their potential for deterring bullying and other bad behavior.

There are no scientific studies backing up the idea that cameras are effective anti-crime tools, but more than three-quarters of public high schools use video surveillance, according to 2007 data published this year by the National Center for Education Statistics and Bureau of Justice Statistics.

Locally, schools in Montgomery, Prince George’s, Prince William and Loudoun counties all have indoor surveillance.

If the Fairfax board approves the cameras, principals will be able to install them in cafeterias and other identified “hotspots” after gathering evidence of community support. Cameras would not be allowed in locker rooms, restrooms or classrooms.

Fairfax officials estimate that installing cameras in all high schools would cost $880,000, plus about $100,000 annually for maintenance. That money would come from proffer and bond funds and from schools’ non-instructional funds — proceeds from vending machines, for example.

Critics have argued that the school system is pushing the proposal along without giving careful thought to the cameras’ long-term cost and their impact on school climate.

“I ask that you put off this decision,” activist Michele Menapace said at a school board meeting earlier this month. “We don’t have good data.”

Even if the board approves the cameras, it may not be the last word in the debate. Evans has resolved to bring the issue up for reconsideration in 2012 — after the next board, including six new members elected in November, takes office.

More on schools:

Fairfax principals want indoor school cameras

Fairfax board to vote on cameras in December