Question juridique clé
Whether A.X. could be held liable as co-perpetrator for the brother's bottle strike in the attempted serious bodily harm count.
Solution extraite
Yes. Co-perpetration can arise through concurrent, even spontaneous, participation during execution; A.X. adopted and benefited from his brother's intervention and continued the assault.
Motifs extraits
The court held that a prior agreement is not required. It is sufficient that the participant willfully assumes the role and, by conduct during execution, makes the other's act his own. A.X. did not withdraw after the bottle strike but intensified the attack with kicks, showing tacit agreement and acceptance of the intervention.