There is a criminal offence here.
It’s him not her although she has aided and abetted this.
It is intentional deprivation of assets with a view to continuing to receive benefits and failing to advise change of circumstances.
I would advise your mother to report this to the benefits agency. She is unlikely to be prosecuted if she gives that information.
If you were to take her to court over this, she could raise the illegality of the money being transferred to get the matter thrown out because the court will not enforce an illegal transaction.
Whether she would be entitled to any or all of this money would really depend on the extent to which she supported him when he was unemployed and how much that was worth and whether there had never been an agreement that this would be repaid.
Regardless, any joint debts he is liable for.
Your mother is going to have to decide how she quantifies the amount of money that she is entitled to and she can put pressure to bear on him bearing in mind the benefit fraud I mentioned earlier. She has to be careful that she doesn’t receive to blackmail him although it should focus his mind.
Can I clarify anything else for you?
I’m happy to answer any specific points arising from this.
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