Can my mother reject a suitor who proposed to marry me because his father is imprisoned for a murder case, and does this flaw the young man despite his religiosity and good character, and is he to blame for what happened, and how can I convince my mother given my father's approval of the young man?

If the young man is religious and of good character, his father's imprisonment does not diminish him, for no one is held accountable for the sin of another, as Allah Almighty says: "And no bearer of burdens will bear the burden of another." The criterion for choosing a husband is religion and character, as the Prophet, peace and blessings be upon him, said: "If there comes to you one whose character and religion you are pleased with, then marry him." Try to convince your mother. If she insists on refusing, and her refusal has a valid justification, then it is obligatory to abandon the marriage. However, if you will not be harmed, or if the harm arises from foolishness, or if abandoning the marriage would harm you, then there is no objection to marrying him without your mother's consent, while striving to be dutiful to her.