I think as a general rule people say that a hit deer will have its tail down. I watched a deer walk by me during gun season, and I let him go as he was walking right to a field my friend was hunting (I had a buck, he did not) so I was watching, and sure enough BOOM, Matt shoots, I see the deer's tail flying high! I waited, he came and got me, he hit it, it was dead about 50 yds from the shot. So they can have their tails stright up. To give you an idea, he hit the ground HARD about 10 yds from where I saw his tail up, struggled up and another 15 yds and that was it.

--Jim