I didn't have the patience to sit through the full 49 minutes but if the professor continued as he started. I.e he would never talk to a police officer. That is bad advice.

"So you say you shot a 'mugger with a knife'. But no one can back up your story and there's no knife.

Now you are telling us you could have pointed out the knife got thrown across the street in the struggle and if we'd looked at the time we'd have found it and his dna on it. But a passer-by must have picked it up since
And you could have told us a crowd saw the whole thing and if questioned could have verified your story?
And you could have told us his cronies were heading up the street and we could have caught them.
But you chose not to tell us any of these things that would have proved your innocence. So what we have is you admitting to shooting a man who we have no evidence was an armed threat to you.
Congratulations on standing up for your right to silence!
Do you like prison food?"

The Sock