in 2008, Ohio adopted a castle doctrine, which allows for self defense in the home, property, cars, etc
"The Castle Doctrine," provides a presumption that the homeowner acted in self-defense for individuals who use force to thwart others who have entered their homes, businesses or vehicles unlawfully. so if you son, asked this person in, he then would have to show that he then asked him to leave and that the cousin did not - but instead, began using the force against your son
it used to be that those who defended their homes against intruders had to prove the perpetrators were close enough to do them harm and intended to do harm. but with this new law, the roles are reversed and the intruder has to prove they did not intend to harm occupants.
you may want to have your son's attorney exam that a bit closer.
i should have provided the code for you - here it is
(A) Every person accused of an offense is presumed innocent until proven guilty beyond a reasonable doubt, and the burden of proof for all elements of the offense is upon the prosecution. The burden of going forward with the evidence of an affirmative defense, and the burden of proof, by a preponderance of the evidence, for an affirmative defense, is upon the accused.
(B)(1) Subject to division (B)(2) of this section, a person is presumed to have acted in self defense or defense of another when using defensive force that is intended or likely to cause death or great bodily harm to another if the person against whom the defensive force is used is in the process of unlawfully and without privilege to do so entering, or has unlawfully and without privilege to do so entered, the residence or vehicle occupied by the person using the defensive force.
(2)(a) The presumption set forth in division (B)(1) of this section does not apply if the person against whom the defensive force is used has a right to be in, or is a lawful resident of, the residence or vehicle.
(b) The presumption set forth in division (B)(1) of this section does not apply if the person who uses the defensive force uses it while in a residence or vehicle and the person is unlawfully, and without privilege to be, in that residence or vehicle.
(3) The presumption set forth in division (B)(1) of this section is a rebuttable presumption and may be rebutted by a preponderance of the evidence.
again, in my opinion, your son will need to show that if the cousin was invited in, at some point, he was also asked to leave - when he did not, he then became an intruder without legal right to be in the residence.
good luck with everything
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