It's understandable that this would be the point you would focus on -- I concede that it's easily the most troublesome aspect.

If someone who has already been tracked in such a way commits further crimes, further punishment in the form of temporary outlaw status is what occurs to me. While I realize the harshness of that particular solution, particularly in context, we have remarkably few viable alternatives to consider, nor do I believe that we could so easily restrain the rage of the more self-righteous in our numbers in such a circumstance. I wouldn't be dredging up a discarded practice otherwise.

They would be internal, yes -- that possibility is precisely why I began giving tracking chips consideration to begin with. Concerning removal, I had hoped that it would be possible to plant them at a sufficient depth at a random and undisclosed point of the body to complicate the matter. Apart from those considerations, I unfortunately have no ideas as to how to prevent their removal, nor do I yet know how to deal with the medical aspects you cite.

Concerning testing, that consideration is one I'm leaving to the engineers.