Ken.
The forensic scientists are not being close minded. They're looking at the scene and the evidence, and then you stray onto the crime scene wearing a duck on your head and declare "IT WAS THE DRACULA WHO DUN IT"
the forensic scientists aren't close minded for what transpires afterwards which goes something like.
scientist: ....why do you say that..and how did you get in here?
duckmanham: yesterday was a friday, the natural prowling time of the dracula!
scientist: i think you made that up, and we haven't determined the time of death, and you didnt answer how you got in here
duckmanham: and does the victim not have a most ghastly wound on her neck? clearly it could only be the work of the dracula!
scientist: the wound in no way resembles bite marks or puncture wounds, it looks like her throat was slashed open with a knife.
duckmanham: thus proving it was the dracula!
scientist: do you have any evidence vampires are real
duckmanham: I have this book
scientist:....damnit i dont have time for this, security!
duckmanham: you're just persecuting me cause i know the truth! stop being close minded! QUACK! QUACK!