Because at that point in time, he is way more of a physical threat than she. What don't you understand about that?
Let's say he keeps your scenario: Focuses on the "suspect". This means he's fighting 2 people, with the stronger having the advantage because he's focusing his attention on the weaker one. Honestly at the point he interferes he's a suspect as well, so again, your goal shifting point is wrong as well.
That makes sense to you? Also, how does he know that guy is 14? He doesn't so stop bringing that up as a point of sympathy or something. He made a grown man action.
SN: Y'all don't even wanna see this chick's FB. She's the prototype for what Coli nikkas hate.
LINK!!!!