Can you file a civil suit aganst some one for a person that has died?
Yes, depending on your status. As an executor or administrator of their estate you can. If you want to sue the person you think is responsible for their death you might be able to under the Wrongful Death statutes in your state; they will spell out WHO (what relationship or status you must have) has "standing" (as it's called) to file a Wrongful Death suit on behalf of the estate and/or the survivors of the deceased.
You should see a lawyer and there is a time limit (statute of limitations) on how long you have to file the suit.
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