Can my mothers Deported husband have entitlement to her life insurance?

Please accept my condolences on the loss of your mother. As for your question, if the life insurance policy had you as the only designated beneficiary, then your mother's husband would not normally have any rights to it. However, if the life insurance is payable to her estate then he may have some rights to the estate and, therefore, to the insurance proceeds, assuming that he survived your mother. If the insurance is payable to your mother's estate, then her Will would control what happens, in general, if she has a Will, but you may still need to address the fact that she was known to have been married at some point prior to her death and may still have a surviving spouse. If she has no Will, and if she has a legal spouse who is still alive and not divorced from her, then her spouse is one of her heirs, along with you and any other children, and those rights will need to be addressed. In short, if you are the only named beneficiary of the life insurance, it's yours. If not, and if her estate is the beneficiary, get a probate consultation with an experienced probate attorney in the state your mother lived in at her death, and find out what you need to do. Best wishes to you.