Recently, blame my luck or whatsoever, I kenna a few accident cases.
When you got an accident case, the thing is, no matter what you do, your boss can say easily that you did not investigate the case properly.
There is endless questions you can ask in a short/long/mostly long interview with the eyewitness or people involved.
Maybe, I am really not doing the correct thing. But I felt like no matter what I do, it will be in the wrong.
Hope my luck turns for better.