You should see an attorney and get a legal document drawn up stating that you are caring for him and that he has assets and could pay. You don't say if he has assets or if he is mentally competent. All of these things matter, but having a legal document is probably the best way to make sure it is done legally.
I've been here and done this. You don't say what these expenses are - is he staying with you and failing to contribute to your utilities? Is he in an assisted living facility and refuses to pay rent? If he's with you, speak to an accountant about claiming him as a dependent on your taxes. It won't help now but will come out in your favor at the end of the year.
If you want him to contribute to YOUR household and he won't then perhaps he should live else where. Helping with expenses is the most basic thing our elder can do. It could be that he feels entitled or doesn't trust you with access to his money. His behavior might only get worse and he could become more obstenant; then you have emotional issues along with the financial ones. If I were you, I'd start looking into alternative housing arangements.
Carol
If you want him to contribute to YOUR household and he won't then perhaps he should live else where. Helping with expenses is the most basic thing our elder can do. It could be that he feels entitled or doesn't trust you with access to his money. His behavior might only get worse and he could become more obstenant; then you have emotional issues along with the financial ones. If I were you, I'd start looking into alternative housing arangements.
How long has you Father-in-law been living with you?
What kind of expenses are you talking about?