Would a tattoo be acceptable as a means of personal Idenification?

No.
That's not professional or valid.

I hope this post was a joke.
Lol.

No.
That's not professional or valid.

I hope this post was a joke.
Lol.

A tattoo can be considered a distinguishing mark if something were to happen to you, they could use the tattoo to tell that you are who you are. That's about it. You can't use it as ID to get beer or anything like that.