Teabag, heartfelt commiserations.
I have had run-ins with Trésor Public and Centre des Impots before, fairly similar to what has happened to you (demands sent to an incomplete UK address which was also 8 years out of date and which I had never received, coupled with the fact that the demands had been sent to me in error - mistaken identity!!). I had to make many phone calls to clear it over a period of days - both to Trésor Public (who are the strong-arm debt collecters, the ones who empty out your bank accounts to which they have complete access), and the centre des Impots, (who have the database with alleged names and addresses of taxpayers).
Unfortunately, the same events occurred again the following year, even though it was all supposed to be cleared up ( names and addresses had allegedly been altered etc). That time, it was even harder to clear it, (different emloyees, more obtuse even than the lot from the previous year!).
My point is that this type of horrendous mistake occurs much more than one would imagine. I have come across a number of French people who have stories of that kind about those absurd and really distressing mistakes.
If it hadn't got sorted for me, I was prepared to "porter plainte" for harassment etc... although not entirely clear as to whether to go to the procureur. What I had started to research then, was the "médiateur de la République" - there is one for each département, and he/she sorts out disputes between the people and the state. For that you have to build a complete dossier, and present it to one of the sub-mediators (I think they might be called senators) who will pass it on.
As for compensatioin being paid, that never happened, even though I had demanded
1) an explanation
2) an apology
3) compensation
which they might have had a good laugh about (some of my French friends thought it was hilarious that I should demand and expect any of these three...)
But I did get my bank expenses reimbursed (on presenting the invoice to the Trésor Public, sending it to a named idividual within their accounts department, who had intimated that yes, I might be able to obtain reimbursement - which amounted to about 100€ for each bank account concerned).
And I have a feeling that you can always utter the magic words of "Tribunal Administratif" - either that, or perhaps the "Conciliateur Fiscal", which some people on this forum seem to have experience of.
Skirmishes with tax offices etc. here are one of the things that raise my blood pressure, as you feel you are really up against a brick wall in situations like these - so I wish you persistence and doggedness to sort it out - they really should not get away with it. The main thing is don't give up, and be prepared to write a number of letters to different people repeating more or less the same thing, send them with AR (of course) - and mention the médiateur or the conciliateur or the tribunal administratif.
Good luck.
The Médiateur de la République site is now in English as well - http://www.mediateur-republique.fr/page.php?lg=en&rub=03
part of that site says:
First of all, before contacting the Mediator of the Republic, you must make an initial approach to the government department concerned - requesting an explanation or contesting a decision - and noted that the disagreement persists. Next, referral to the Mediator of the French Republic is not direct: you must go through the intermediary of a member of parliament, deputy or senator, of your choice. You put together a full dossier, with a clear account of your problem and all the documents relating to the case. You hand this dossier to the deputy or senator of your choice and he/she will pass it on to the Mediator if he/she thinks it appropriate. However,the Mediator of the French Republic's delegates can settle a large number of problems directly and quickly.You can arrange to meet one of the delegates from your department by making an appointment over the phone or by going in person to their office - ie at an easily accessible organisation(legal information centre, public services centre, community welfare centre, etc) or to the prefecture. If the delegate cannot settle your problem, he/she helps you to put together your dossier and directs you to a member of parliament who will pass it on to the Mediator of the French Republic.
I read (with some delight) about your success with the conciliateur, Parsnips.
I should have mentioned that in my case, the Trésor Public chasing me were from a département other than the département where I live - which is why I did not try to go this route - but you are right, it is the first port of call under more "normal" circumstances. Thank you for mentioning it.
A more positive experience:
We moved from one french house to another nearby in 2006 and I wrote to the Tax F. people telling them to stop taking the monthly installments from our bank account. But they continued to do so after we moved for a few months.
I went into the office when I realised what had happened. They sorted it out and I got a complete refund quite quickly.
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