Stumbled upon this older FBI article, but I found it still pretty interesting and contains a lot of potentially helpful information for vendors and customers. It explains the entire LE process step by step pretty much.
https://www.thefreelibrary.com/Profil...ges-a018447923
FBI Law Enforcement Bulletin: Feb. 1 1996 written by Gerald Vajgert
I think a lot of the tips here are things we discuss regularly but there's never anything bad about rehashing the useful stuff!
Everyone should read the whole thing but here's a tl;dr that the article itself made. This completely skips the investigation phase of the process, which they outline, but if you wanna get a preview here it is:
Postal inspectors use these criteria to identify packages that might contain drugs.
Package Criteria
Emits odors of marijuana or or a masking agent (e.g., coffee, perfume, fabric-softener sheets)
Is heavily taped along seams
Is poorly prepared for mailing
Appears to have been re-used
Has an uneven weight distribution
Label Criteria
Is handwritten
Contains misspelled names, streets, or cities
Originates from a drug source State
Has been sent from an individual to an individual
Contains return address ZIP code that does not match accepting post office ZIP code
Shows a fictitious return address
Lists sender's and/or receiver's names of common type (e.g., John Smith) that are not connected to either address