With permission from Reddit user Betaateb, here is his indepth theory on who really murdered Teresa Halbach:
Motive: Jealousy and hatred towards Steven Avery. The frame is on!
Means: Hunters with plenty of weapons available(including a .22 rifle that Scott tried to sell in the days after the murder), as well as weak alibis from each other only. It was their car that TH was on the property photographing, surely they knew she would be there.
Opportunity: With their weak alibis there is nothing to prove these two didn’t drive off the property and sit in wait for TH. They are familiar with the gravel pits, where the second burn site is located. Clearly they have intimate knowledge of the Avery property.
The narrative that makes the most sense to me is they sat in wait for TH, captured and killed her (with their histories there certainly could have been a rape involved as well, but that cannot be proven one way or the other). They put her body in the back of her car and drove her to the gravel pits where they burned her body. They take the fire barrel from behind their house and load her ashes into it (missing a few pieces). They leave her car on the property in a place where it will be found, and quickly. That property was huge, there were plenty of places that car could have been hidden far more successfully (not to mention the crusher, which may have drawn unwanted attention in the middle of the night). They dump TH’s ashes into the fire pit where Steven had a bonfire earlier that night, and put the fire barrel back behind their house (leaving ashes and small bone flecks in the barrel).
They know that when the ashes of a dead woman last seen with SA are found in his fire pit that that railroad is going to leave the station full steam ahead.
Scott and Bobby’s roles in the murder and the case have basically come to an end, outside of their aggressive testimony against SA ,of course, in which Bobby is caught in a lie trying to make Steven look as bad as possible.
Now is when the Manitowoc count sheriffs department step up to the plate. They had nothing to do with the murder up to this point, but they see if for the opportunity it is. A chance to bury a $36 mil lawsuit, and put away a guy who had humiliated the department.
Colburn performs an illegal search of the Avery property and finds TH’s car, calls it in to dispatch to make sure it is the right one clearly reading the license plate off to the dispatcher and then describing the vehicle. He knows he can’t do anything with that evidence so he pulls out a screwdriver, removes the license plate (just in case any questions come up about him reading off the license plate number to dispatch) bends it up and throws it into a nearby car, grabs the key out of the ignition (maybe, possible the key is actually TH’s spare, possible the brother/ex/roommate is in possession of it). The Manitowoc sheriff department approaches Mike Halbach and Ryan Hillegas with some ill gotten info. They tell them where to find TH’s car on the Avery property, making sure the people sent to find it have a camera on them to record the find. A find that happens within 20 minutes of showing up to search a 40 acre property for a single car in a salvage yard of hundreds (thousands?). Admittedly the car isn’t well hidden and is towards the front of the property. Does that hurt or help this theory though?
Calumet county sheriff deputy is “guarding” the site of TH’s car, except at some point Lt. James Lenk “sneaks” by the guard before he begins logging anyone visiting the scene. While Lenk is on the scene the deputy begins logging visitors so he signs out as he leaves the scene at 2:41 pm (he testified in court that he wasn’t on the Avery property that day until after 6:30 pm, signature proves that testimony false). What did he do while at the car? Plant blood evidence perhaps? The magic blood evidence that the criminal mastermind SA leaves behind after cleaning the car of any of his fingerprints and hair.
Now the state has physical evidence linking Steven to TH, and blood no less! Looks like an open and shut case. Just in case though they figure they better plant the key to the car was well, it plays well with the story that SA was hanging on to it so he could destroy the car later when him using the crusher wouldn’t be out of the ordinary. Of course you don’t drive a car into a crusher, you would use a front end loader for that job so SA really has no reason to hang onto the keys at this point (the car was parked a few hundred yards from the crusher initially), maybe it is his murder trophy!
Lenk done yet? Not quite yet, they haven’t found a shred of TH’s DNA in the proposed sites of the murder, neither SA’s house nor garage. Better plant a bullet with a smidge of TH’s DNA on it in the garage, just to remove any doubt. The expert in the trial mentioned she so no blood on the bullet, but found nucleated cells. Blood is not nucleated, so whatever DNA sample was found on the bullet wasn’t blood. Consider that for a second, a bullet that supposedly went through TH has no blood on it, but does have some amount of skin or hair on it. Odd. Of course to believe that piece of evidence we have to believe that Steven is capable of cleaning the rest of the garage to the point where there isn’t a single spec of blood, not even deep down in the large crack in the concrete running along nearly the entire length of the garage. Not only is he capable of scrubbing every ounce of TH’s blood and various DNA from the garage, but he is able to do it without cleaning up the various oil stains, and the dirt and grime you would expect on the floor of a garage. Also managing to leave plenty of his DNA on everything in the place (miracle bleach! Genetically programmed to only destroy TH’s DNA evidence! SA is truly the greatest criminal mastermind the world has ever seen).
I am sure I left out plenty of other details we could tear apart as well, but I think that story I just told would be plenty to get a not guilty verdict! Of course the defense wasn’t allowed to bring up any potential third parties because they failed the “Denny” test where you have to prove at least two of motive, means, and opportunity. Clearly the motive is circumstantial, you aren’t proving that they did it because they are jealous of Steven ever so you through that one out. So you have to prove means and opportunity, means was certainly there two men with a gun would have no issue murdering an unsuspecting 25 year old woman. Opportunity is difficult, they only have each other as an alibi though, and considering in the rape case of 1985 16 alibis for Steven were thrown out because they were family I think it is safe to assume the court shouldn’t have any issue throwing out their alibis on the same grounds. Of course that doesn’t help the state prove Steven did it, so why would they want to do that?