Your mother had to give it to him. I see you say she has dementia. The only way he can have her POA is if she gave it to him. She can choose again by giving it to another. Get her to a certified elder attorney and discuss her financial and medical wishes with the attorney so that she understands the ramifications of her decisions. As long as she understands what she is doing at the time she can sign the POA.
If she has Dementia she cannot assign POA. Do you know who the lawyer was who drew it up. If so contact him. Show him doctor proof of her Dementia and the warrant for his arrest. Maybe he can revolk the POA. But if Mom has Dementia she Can't assign u either. You will need to get guardianship and that cost can be taken out of Moms funds.
JoAnn I know you have posted this before, but it is simply not true that a diagnosis of dementia disqualifies one from making or revising a POA document. As 97yroldmom says, it is a matter of what the person understands at the time of signing. I know this because my husband assigned a POA when he definitely had a diagnosis of dementia. The lawyer explained the document to him. She asked him what it meant. He said, "It means that Jeanne can make decisions for me if I can't." She asked him if that is what he wanted. He said yes. Done deal. Didn't matter that he couldn't tell you if he had eaten that day or that by tomorrow he wouldn't remember that the lawyer came to our house. He understood what he was signing at the time he signed it.
"Dementia" covers a huge range of cognitive impairments. Some people with dementia cannot even safely decide what to eat, or they might have toothpaste for breakfast. Others can decide on what they want in their wills and who they want for POA.
Someone whom the courts have deemed incompetent cannot enter into legal contracts, but not all persons with dementia are legally incompetent.
Here are a couple of AgingCare expert articles on the POA subject:
"Dementia" covers a huge range of cognitive impairments. Some people with dementia cannot even safely decide what to eat, or they might have toothpaste for breakfast. Others can decide on what they want in their wills and who they want for POA.
Someone whom the courts have deemed incompetent cannot enter into legal contracts, but not all persons with dementia are legally incompetent.
Here are a couple of AgingCare expert articles on the POA subject:
https://www.agingcare.com/articles/elder-cant-sign-will-trust-power-of-attorney-153521.htm
https://www.agingcare.com/articles/things-you-can-and-cant-do-with-poa-152673.htm