So if Jeremy wore gloves whose are the partial prints on the bullet cases ?
He wore glove to commit the murders, loading bullets with gloves ins a pain which in part is why he made up the tale about loading them and dumping them out. So that if his prints were feound on the ammo it would have an innocent explanation.
I am going by Mike's word partials were found I don't know if that is true. He claims that there was some glue that stuck to the cases. It only sticks if there is oil from fingerprints to adhere to. But anyone who picked up the ammo at any point can leave oil on a casing. Someone innocently handling bullets before they are ever loaded and used by someone else could leave their prints potentially. Which is really what Jeremy was claiming. Prints are not that easy to lift though off casings. The larger the casing the better the chance.
You need gloves when using a weapon, any weapon and being around blood. If you leave a fingerprint or footprint or anything similar in a victim's blood you are screwed end of story. It is worse than leaving your DNA (unless you claim to never have been at the murder scene ever). If you leave a print in blood then that proves you were at said crime scene at the time of the murder.
The only way defense lawyers can try to deal with such is to claim the person found the body right after the murder and thus the defendant got blood on himself and then left the print. Most of the time that argument is not going to help carry the day. You need other evidence to get someone to buy that.
This is why criminal like rubber gloves and the booties doctors wear on their shoes to prevent making footprints. Also to dispose of clothes that get spatter on them. Spatter gets on you during the actual shooting/beating/stabbing/axing. You can't say you happened across the body later if you are found with spatter on you. It proves you either did the action or you stood right next to the victim as it occured.
So successful criminals use gloves, booties and dispose of the clothing they worse.
Jeremy went wrong in telling Julie before and after, using the suppressor, having to shoto her twice, opening and closing he bible to try to figure out how he wanted it and worst of all making up the story about Nevill phoning him so calling police instead of pretending he was in bed at the time of the murders and knew absolutely nothing when the bodies were found. A passive frame is one thing. When you do an active frame then if the frame blows up you are holding the bag. That was Jeremy's greatest error.
You have to be like Sgt Schultz in Hogan's Heroes, "I know nuttzing"