Help with Chapter 8 "Report" bonus title

[souryuu5]

I'm having trouble completing the bonus title for Chapter 8 "Report," where the Duchess gets the butler arrested, but the Duke is not home. Any help here is appreciated!

[Papa Shifty]

Hint: the detective needs help to know who shot the gun
Full:
the duchess needs to see the butler have the gun, then tell it to the detective before he murders her

[souryuu5]

Originally posted by Papa Shifty:

Hint: the detective needs help to know who shot the gun
Full:
the duchess needs to see the butler have the gun, then tell it to the detective before he murders her

Thank you very much! Got the bonus title!