Norma is a good police officer, so she couldn't believe that such experienced worker could fall from that height. Investigate the case and find some clues, that may help you to understand.
What is the best way to investigate a case? A good police officer knows that you must trust nothing, but facts only. Collect enough information about the accident and make sure you have enough evidence to prove your rightness. First of all, you need to look at his personal items.