Here is a comment from Deb Esman. I'm sure it's more accurate than my origional identification of young Mule Deer.

Hi Mike-- My only comment is that I suggest that the fawn is a mule deer/black-tail deer hybrid. As the black-tail deer is considered a sub-species of the muley, this point is probably negligible. Note the dark strip down the top of the tail to the tip. A straight mule deer has only the black tip, the rest of the tail being white. Deer on the east side of the Cascades are considered mule deer, with black-tail being on the west or "dark side" as we like to call it. Here in Kittitas County we see many hybrids as you head up the eastern slope of the Cascades. Deb