Can customs problems cause SSSS to be printed on boarding pass afterwards?

Question

I was flying from Europe to the US. I waited in line to get my tickets (one from Europe to Canada and the other a connecting from Canada to US). The security check seemed normal for the first flight and there weren't problems until I got to US customs in Canada. I had forgotten to declare something that I had bought at a duty free store in the airport and apologized but then was sent to a separate area for more screening.

They did end up taking the chorizo I bought at the duty free store (I should have known better) but I was not fined. After that I noticed SSSS marked on my boarding pass (could have been added earlier I'm not sure). At each subsequent check point, my boarding pass was highlighted with a different color or given a special stamp. I am worried now that I'm on a list of some sort that is linked with my passport and that I will now have difficulties traveling in the future. Do you think the secondary inspection for customs would cause the label "SSSS"?

I then had problems the rest of the way home. I have flown international before and most of the flights we booked for this trip were one way as we weren't flying from the same places.

Is it possible that SSSS was added to my boarding pass at customs or was it added when I originally received it and did not notice it?

Answer 1

It sounds from your story that you were sent to secondary inspection at US customs and immigration, not secondary security screening at security - that's 3 of the 4 S's, the 4th being Selected or Selection.

Secondary inspection at US customs and immigration (preclearance if you're in Canada; on arrival if you come from elsewhere) involves searching your possessions (carryon and checked luggage) for items that shouldn't be brought into the US or indications that you shouldn't be let into the US (for example if you've brought items that indicate you intend to work there, or to move there indefinitely.) It would be trigged by something like a mis-statement on a customs and immigration form (forgetting your duty free). In contrast SSSS, as described in the linked question, happens at the Xrays and scanners station and involves searching your body and your carryon for threats to the flight, airport, or fellow passengers. Very different.

Without knowing what problems you had the rest of the way home (checkin vs security vs customs or immigration) it's hard to know if your name has been associated with a need for more scrutiny, but I find it highly unlikely that an interaction with customs and immigration whose result was to let you in without fining you or confiscating anything could have such a knock-on effect on future travels. I've been to secondary inspection on more than on occasion when entering the US, and it hasn't been the source of any later problems or issues.