Disclaimer:
I don't know if this will hold up in court.
"Those persons accepting these materials in trade certify by in fact accepting said materials that they are not: A local, village, town, city, county, state or federal law enforcement officer, nor an inspector or official of the United States Postal Service or Canadian Postal Service; An agent of the recording arts industry or representative thereof; or an agent of any organization that may desire to prosecute or harass any individual. By accepting these materials, said persons agree that the terms set forth above are done so in a legally binding manner, and certify that they are not accepting these materials in trade as evidence for such purposes."
By the way, I did rip this off of someones page, sorry I forget who you were.