titles of nobility

This important amendment was destroyed in the war of 1812 by British Government.

Now the reason lawyer would have been prohibited is because the International Bar Association was charted by the King of England and headquartered in London. So any American lawyer who uses the term Esquire would be in violation of the Constitution, Article 1, Sect. 9. But since there was no penalty for this, it was largely ignored. This would also be pretty defunct today, as most of our lawyers belong to the ABA, or American Bar Association, so only fools who belong to the IBA would fall under this domain. So basically, unless you accept a foreign title, say Knight, you will not be affected and forced to forfeit your citizenship.

http://www.dailykos.com/story/2007/07/10/356123/-The-Missing-13th-Amendment-an-odd-Constitution-story