No. Not even close.
It's criminal stupid, but it is NOT by any stretch cruelty.
In other words the dog should of known what a gun can do and ignored the command from its master? Have you ever owned a dog?
I would say its criminal and cruelty.
If the dog is trained to attack and the man commanded the dog to attack, wouldn't the dog be considered his weapon?
And its cruel because the dog is just doing what it is told to protect his master. The dog doesn't know that police have guns and will surely shoot it. Its cruel for the man to send the dog in, knowing it will be shot.