They didn't detain because of probable cause.
That's FL, this is OH.
Shooting at Dayton Gas Station, 2 suspects approached car and tried to rob and beat the man. He had a Glock 36, turned and shot one twice. Got in the car, drove away and called 911.
When cops arrived he came back, and was detained for the night. After reviewing video evidence, he was released b/c of self defense.