What is Amelia's special talent???

Because Jolie stopped the train etc., Denzel realizes that she is a born crime scene investigator - actually his potential heir apparent, the new hope of the NY Police! Denzel sticks to her, she is the one who is allowed to check any crime scene. Jolie goes there and thanks to her exceptional sense, she brilliantly finds the things which the killer "left behind" in a conspicuous place. E.g. a match-box or a bolt. I mean, any ordinary patrol could have found those things - where's the special knowledge??? Finding unintentional tracks, now that would have been okay!