I don’t know much about the breed but according to the American Kennel Club, at the top of the entry, the breed is defined as “Smart, Confident, Hardworking.”
http://www.akc.org/dog-breeds/belgian-malinois/
Could be abusive training or handling. Who knows? Or the dog could just be burnt out and turned mean.
I have done some hunt training with my dogs with a man that also helps the military train attack dogs. The military uses the Belgian malinois because, according to the trainer, “their favorite thing to do is bite.” Our military guys that use them send the dogs in first and know to stay behind the dogs because the dogs go after whatever is in front of them once they’re released.
Well, not to characterize a breed, but the Mals that I have been around in the schutzhund/IPO world can be a bit touched. And, from what I understand, the not-so-good ones end up on police forces (i.e. not suitable for the sport for one reason or another).
And, knowing quite a few K9 officers, they are generally not the most suitable sorts of handlers for most Mals. I wouldn’t write this off as a bad dog without knowing more about the handler, the training of both, and the circumstances.
I think they are pretty similar to German Shepherds, but Malinois are leaner and more agile, Shepherds are stockier and tougher.