NYC Mayor Guilty of Criminal Intent?

It seems that NYC Mayor Bloomberg is breaking the law by using "straw" buyers to purchase guns in other states. Most recently people working for the mayor were in Arizona at a gun show to conduct a "sting" of gun purchases. One, it is illegal to purchase firearms through a third party, secondly it is a crime to purchase a firearm for another person. Both of these are regarding a licensed firearms dealer, but it is no one's business for a private citizen to sell their legally owned property. If Mayor Bloomberg's employees bought guns from licensed dealers for Mayor Bloomberg with Mayor Bloomberg's money then shouldn't they all be arrested by the BATFE for violations of the law? Next, why does Bloomberg think he has the authority to do anything in another jurisdiction? Just because he bent NYC law to remain mayor does not mean that he is the dictator of anything outside the 5 boroughs of NYC.