One of CBP missions is to ensure that travelers entering the United States comply with U.S. laws. In support of this mission, CBP conducts random compliance examinations (COMPEX).
Essentially, COMPEX examinations involve random selection of vehicles and/or air passengers that ordinarily would not be selected for an intensive examination. By combining the results of these examinations with the results of targeted examinations, CBP is able to estimate the total number of violations being committed by the international traveling public.
When CBP compares the results of the two types of examinations, we are better able to devise enforcement techniques that prevent the entry of contraband without creating undue delay of law abiding travelers. Often trends tell us what message we need to send to ensure informed compliance by travelers who were unaware of our requirements.
It is possible that, upon your entry into the United States from a foreign country, you may be selected for a COMPEX examination and experience a slight delay in your Customs processing. CBP believes that this compliance examination is a critical component of our ability to ensure that our processing procedures are effective. We apologize for any delay or inconvenience you may experience and appreciate your cooperation.