Originally Posted by guest666

You are strictly correct in the observation that possession of citizenship is not equivalent to its acquisition, which, in turn, implies that the fact of acquisition would have to be established by the authority. THAT BEING SAID, the discovery of the fact itself may very well lead to scrutiny upon passport renewal, which effectively may mean a loss of citizenship. Unfortunately, there is absolutely no way to distinguish raging paranoia from a very reasonable fear as there is absolutely no information on what kind of screening is happening at the time of passport renewal.

Up until eTA, it was clear that not a single entity outside of Canada knows about my Canadian citizenship because the passport was simply not seen by anyone but Canadian border agents. The eTA has really changed it all. My only hope was if someone could confirm that the Canadian passport shown at the check-in is only submitted to Canadian authorities through an internal protocol and has no reflection in the databases of the country of departure. From what I have read on this forum and legal documents, this is likely not the case. And I'm not ready to bet something as valuable as citizenship on the chance that travel databases may not be interrogated for this purpose. Alas, I am probably looking at a life of 20-hour flights through Mexico, North Africa, and the Middle East. Not the way to live, but it's the lesser evil.

Originally Posted by airoli

I have a resonable understanding of PNR management given my professional background. In a simplified way, here's what's happening:

When an airline agent (human or digital) tries to check a passenger in for a flight to Canada (or the US or many other countries), it must submit the passport / citizenship information to the destination country's authorities. The data is added to the PNR and the PNR is submitted. The destination country's system then sends back an "ok to board" message.* Only once that message is received can a boarding pass be issued and a passenger board the aircraft. You can sometimes see a remark "DOCOK" or "ADOC" on your boarding pass. The passport data stays in the PNR and the PNR can also be accessed by the governments of the departing country (or Schengen zone), transiting countries, and probably many others more (including the US on almost all itineraries).

For flights to Canada, the Canadian ETA system will not issue ETAs for non-Canadian passports held by individuals identified as being Canadian citizens. Therefore, Canadian citizens cannot use a passport that requires an ETA to board a flight to Canada. The only passports not requiring an ETA are Canadian and American. Which leads to the conclusions described in the FAQ above: As a Canadian citizen, you must use a Canadian or US passport to board a flight to Canada. And that data is visible to all governments somehow affected by this PNR.

Note: A PNR includes all segments of a ticket. So if you book FRA-IST-YYZ on one ticket, and add your Canadian citizenship in IST to obtain the boarding pass to YYZ, it is still stored in the PNR to which the Schengen / German authorities have access.

As I wrote upthread, if and to what degree Schengen countries go comb through this massive heap of data, track it back to their citizens, screen for dual citizenship violations, and then take action against them, is a completely different subject.

*In the absence of the ok from the destination country, you may sometimes get a "this is not a boarding pass - your documents must be inspected at the gate" type of document that allow you to go as far as the departure gate where the trained agents sit, but not on board.

Originally Posted by commaspace

You're doing a lot. Government don't go around and check for dual-citizenship violations on flights to ANOTHER country. Use your CAN passport to go to CAN and your European passport to go to EU. If they want to, they can see where you have travelled even with your creative routing. If you want to be 100% sure, give up one of the citizenships. Otherwise, stop being paranoid.

Originally Posted by Covidian98

Also, even with access to the travel passport info in the PNR database, the level and type of access may be restricted.

For example, a country may need a justification to access the database. Additionally, they may be able to access a single PNR based on some ID (like name and date), but they may not be allowed to do BULK searches to retrieve data on all passengers flying out of the country.

There is a fundamental and huge difference between single record access (using a key/value request) and a bulk access (using a general query based on some criteria). My point is that to be able to find people with dual citizenships, they would need BULK access (which by its nature is not very restrictive, and may potentially violate a lot of privacy laws), and they would basically need to perform this search regularly on an ongoing basis. So that sounds a little implausible, although still theoretically possible.