Oh, I've just had a thought of total randomness (yes, I've probably got too much time, and yes, I spend waaay too much time playing with legal materials). Ed says that it's not his first investigation, blah, blah.

It then occurred to me that modern democracies have a separation of powers between investigator and judge for a reason. Yes, Narnia isn't a democracy, it's a monarchy, but what's to prevent a misuse of power if the Just King is emotionally invested (which he is with Morgan). Leo ex machina? The fact that he has to justify himself to his sibs? Just his innate desire for justice?

Yep, totally random : )