WHITE PLAINS, N.Y. – It’s getting to the point where teachers union members would be wise to demand a detailed annual report of exactly where their dues money goes, and insist on seeing the receipts.

That’s because, far too often, it’s ending up in the pockets of corrupt union officials.

At least half a dozen times per year, EAGnews reports about new cases of embezzlement by local teachers union officials throughout the U.S.

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The latest case comes from White Plains, where an assistant high school principal has pleaded guilty to stealing nearly $800,000 from teachers union back accounts when he was a local union treasurer.

Frank Gluberman stole the money by forging the union president’s name on checks made out to himself and his daughter between 2006 and 2013, according to CBS New York.

Gluberman, the current assistant principal at Woodlands High School in Hartsdale, New York, pleaded guilty to a charge of grand larceny Wednesday and will be sentenced Dec. 14, according to the news site. He could serve up to 15 years in prison.

The frequency of these type of thefts raises a lot of questions.

What type of internal accounting procedures do most local unions have in place to prevent massive embezzlement? It seems like someone should have noticed hundreds of thousands of dollars missing in the New York case before seven long years passed by. Were other union officials turning their heads and pretending not to notice, perhaps in exchange for kickbacks?

We also have to wonder about the quality of people who seek elected union positions. It’s highly likely that only a small percentage of these thieves are caught. There’s probably many more hands in the union cookie jar than anyone ever imagined.

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Of course, in the end, this is a union problem. If these labor organizations want to maintain any shred of public respect they will do whatever it takes to clean their acts up. Such an effort would probably have to start with rank-and-file union members who are fed up with the corruption and decide to replace their leadership and demand financial accountability.

But do most rank-and-file members care enough to organize and take action? If they don’t they can only blame themselves when money repeatedly comes up missing.