Well it seems to me the most damning evidence is the misssing knife and parka coat.
All the reseach into eye witness testimony shows it is unreliable
Teenage boys go through phases (think Kevin) so I'm not buying the urine in pots (even if true), Goth gear, a fondness for Marilyn Manson and the black dahlia etc.
If it was Luke I’ve always thought he could easily have dumped both the parka and the knife in any bin on his way home, the bins were emptied the following day and bin lorries never checked.
But the question is did he own a parka before. Eyewitnesses say yes but IMO they could be mistaken. If someone had a photo or cctv or something to prove he had a parka then that would be enough to convince me and most others who are not sure, that he is guilty. Did the police check cctv from shops in the area etc to find a picture of Luke in his parka before the murder, how much went into the search for the coat? I’m just not convinced there was a parka, so reasonable doubt for me on that.
Missing knife, I will need to check the book to see what was said on that, from what I remember, I’m sure someone will be quick to correct me if I’m wrong, the knife missing from the pouch that had the writing on it, the knife would be too small to be the murder weapon. Another knife that was meant to a missing knife, was found by Luke’s mum and handed to the lawyer who gave it to the police so no longer missing.