Conspirators scrape the silencer along the mantle
https://youtu.be/-EDp_tqUysI?t=9m54s
I have also analysed this using logic and probability ...
Ask yourself which is more likely ...
His sister shoots all his family ...
Separately his relatives plant a silencer to frame him ...
Separately his girlfriend decides to frame him ...
or
one person (or group of people) were responsible for all three things
ie the shootings, planting the silencer and persuadig his girlfriend to frame him ...
It is clearly more likely that one person (or group of people) were responsible for all 3 pieces of Jeremy's bad luck ...
Your opinion of the character of the relatives may have clouded your logic up until now ...
What do you (or anyone else)really know about Anthony's character for example ?