As has been said by others, your cop friend is 100% wrong. That type of riding creates a life-threatening situation needlessly, when the information on how to ride safely in traffic is a two minute Google search away. Not only that, but as a member of law enforcement, he is also giving cyclists a very bad name by breaking the law he is sworn to protect.

Here are a few links that will get you started on why you should not be riding against traffic and what the traffic laws are pertaining to bicycles are in each state. They explain exactly why riding on the right hand side of the road is the correct and safe way. If I were you, I would show this information to your cop friend; I would hate for a member of law enforcement to be injured or even killed as a result of being misinformed on the risks involved in what he is doing.

http://www.bikeleague.org/resources/.../roadrules.php

http://www.massbike.org/resourcesnew...ate-bike-laws/

http://www.kenkifer.com/bikepages/traffic/wrong.htm