discussions : Dog Biting and Mouthing

I Recently had a 3 year old German Shepherd taken away from me and killed by the City of Ogden, Ogden, Utah He was playing with my children in the yard and bit a couple children....not bad bites kinda nips but did break the skin...so had to be quarantined for 10 days...that made him so crazy!!!...when I picked him up out of quarantine the Animal Services said I had to have a muzzle on him at all times...except in the house!! Is this appropriate for his playing around??