I can only comment on Canada, but the US is similar in that their postal service/mail is a federal operation. In Canada, it is a federal crime to interfere with, open or steal mail. This goes for postal employees. I've seen cases where the delivery driver can clearly smell marihuana, so its turned over to Police, who can obtain warrants, etc. Or they have a drug sniffer dog ID packages. These steps are taken because employee's cant just open packages on a whim or they are breaking the law. You have a right to privacy. You should be able to access Fed Ex department policies and cross reference with the USPS laws. If they are the same, then it should be a technicality that your rights were violated, therefore, charges get voided. Then again, the US is known for having a tougher justice system in Canada, so my comments can't bear too much weight. Best of luck though. And if Fed Ex did break procedure, I'd suggest you launch a civil suit on them.