Everett School District officials can and should put to rest any lingering controversy over the Kay Powers case. It may be as simple as answering one question:

What was the cone-shaped object that several teachers report seeing in the ceiling of Powers’ classroom last spring?

In the absence of a straight answer, the district invites speculation that a video camera was secretly watching Powers and her students. The legality of such surveillance is dubious; the public trust implications unsettling.

To recap: Powers, an English and journalism teacher at Cascade High School, was fired in November after she helped students produce an underground newspaper on school equipment during school hours after being told not to do so. Powers appealed. Before an open hearing was to proceed earlier this month, she and the district reached a settlement that allows Powers, 65, to teach English at Jackson High School until August 2009 and provides her back pay.

Now the teachers’ union, which backed Powers’ appeal, alleges that the district was spying on her classroom while it was investigating her. The district’s investigator testified under oath that she had no knowledge of video surveillance, and the district’s attorney in the case said it never took place.

Fine. But to completely clear up the matter, the district needs to account for the object seen in the classroom ceiling, described by a teacher as a plastic casing about six to seven inches long with a glass rectangle on the bottom. A private investigator who was shown a drawing of the object by one of Powers’ attorneys identified it as a “passive infrared motion sensor” that was “commonly used for video concealments.”

The object was first noticed by teachers shortly after the district launched its investigation of Powers last May. After several teachers had noticed its presence, it disappeared in early June without explanation.

Perhaps it was put there by a student or staff member. If it was put there by district officials, there might a reasonable explanation. Whatever it is, a full answer is required. Teachers, students and parents deserve one.