No one can tell you why they need an affidavit other than them!! If you don't get one for them. they may not take the car back!!
In no way am I offering you legal advice, and in no way has my comment created an attorney-client relationship. You are not to rely upon my note above in any way, but insted need to sit down with counsel and share all relevant facts before receiving fully-informed legal advice. If you want to be completely sure of your rights, you must sit down with an experienced criminal defense attorney to be fully aware of your rights.
Whatever your mother owned at the time of her death now has to be passed on. In other words, title has to transfer.
A will tells the probate court how the court should transfer title to the items mentioned in the will. The actual passing of the title is done by the probate court.
If your mother's estate was small, you can complete a small estate affidavit and this will allow you to deal with the issue of the car.
Getting the small estate affidavit may be a minor hassle, but it will allow you to avoid larger hassles.
I am licensed to practice law in Michigan and Virginia and regularly handle cases of this sort. My answering your question does not establish an attorney-client relationship. You should consult a lawyer so you can tell the lawyer the entire situation and get legal advice that is precisely tailored to your case.
Why they need a small estate affidavit is not clear. Your mother's "estate" has no interest in this vehicle. On the one hand, getting the affidavit is a very simple thing. You can download one, here: http://courts.mi.gov/Administration/SCAO/Forms/courtforms/estatestrusts/pc598.pdf
You would need to get it notarized, but that is no big deal, either.
If you do not provide them an affidavit, it is anyone's guess what happens. If they do not accept the car, you have no obligations to them. The estate does, potentially, but the estate does not exist. I think you are at an impasse, then, and it would be up to US Bank to figure out how it gets its car back.
Their position is ludicrous. If you want to make a point, you can refuse their demands and let them figure it out. If you want to just not deal with this anymore, then download the affidavit and let them go away happy.
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