EU-Schengen citizen getting Schengen stamp despite travelling with EU document, change in how rules are applied or just inconsistency?

Question

I am a dual Italian, British citizen. When I travel within EU+Schengen+UK I usually carry with me my Italian ID card and my British passport (I leave my Italian passport at home, since it's bulkier and more easily ruined than a plastic ID card). Even without a UK passport, Italian ID cards are enough to travel to the UK until December 2025.

As is common, I usually show my UK document to UK authorities, and Italian document to Italian authorities. I might use either document for the airline (but when flying from Italy to the UK, I pick the UK passport, since otherwise the airline might want me to show them my settled status).

Something weird happened a few months ago: I showed my Italian ID card to border control, and the Italian police asked me to show them proof that I would be entitled to enter the UK. I pointed out that I was also a British citizen, but a UK passport wasn't needed since settled status was also enough, but they replied something along the lines of:

It's not that we want to be nosy, we just need/want to check that you'll actually be able to travel to where you're going to

That was perplexing, since I understand that to be the airline's responsibility, not the outbound's border control. I anyhow presented them my UK passport.

A couple of weeks ago at the same Italian airport (Linate), I was again asked to provide more proof, after showing up at the border control with my ID card. I then handed them my UK passport and...

They stamped my UK passport. This feels silly and a waste of passport space, even more so because the stamp was perfunctory (you can barely see that it's an italian stamp, no legible indications of the airport).

My understanding of the situation is:

• It's a similar one to EU residents getting a EU stamp and it's technically possible and probably not unusual for a EU citizen to get their non-EU passport stamped, but it seems very unusual when the border control saw your EU document.
• It could be possible to avoid dealing with inconsistent application of the rules by border control police, by using the e-gates either with a UK passport, or even an Italian ID card (for ID cards emitted after 2018, but only if travelling to a few countries). But unfortunately I won't be able to do that when going through border control together with my non-EU spouse (since their citizenship doesn't allow them to go through e-gates).
• To address the concern of avoid waste of passport space, I can just ask them to follow my directions and not stamp, though my request might be ignored.

Did Italian and/or Schengen border police change the way that they're applying the rules? Is this just inconsistent application?

Is it more likely to happen in certain airports than others (Linate, in this case), maybe because of how prevalent flights to some countries are in different airports (i.e. rules for travelling to UK with ID card are less obvious than for travelling to Ireland, so if the airport has more/less flights to UK/Ireland, their border control might be more/less surprised in seeing travellers with ID cards)?

Is presenting only an ID card when travelling now frowned upon by border police?

Answer 1

It's pretty clear that they shouldn't have stamped it. I would probably try asking them not to stamp before handing over the UK passport; you can explain that you're trying to conserve blank spaces and then if they refuse (and you haven't antagonized them!) they can at least try to stamp over another Schengen stamp. By asking before giving them the passport, you reduce the likelihood of their stamping it out of habit.

The Schengen Borders Code is explicit that passports of EU citizens are not to be stamped. It is not explicit about the case of non-EU passports held by EU citizens with multiple nationality, but it's certainly consistent with the spirit of free movement law and with the administrative requirements of immigration and border control to conclude that a non-EU passport should not be stamped when you have also shown your Italian ID card.

If Italian police have newly started asking about your ability to enter the UK, it could indeed be because of a change in their policies (whether with respect to travel to the UK in particular or to non-EU, non-Schengen destinations in general); I don't know. But about the stamping, I would only say that policy changes in recent years, in the countries I'm familiar with at least, have generally been in the direction of less stamping than more.