Another aspect of Girl X's alibi has struck me as off for a while and I've realised why.
She walked a considerable distance from the bus stop with Brianna and Boy Y to Linear Park. They sat on the bench. According to her story, she wanted to keep Brianna in the park, supposedly because they don't hang out much and she really wanted to see Brianna. That's why (supposedly) she was spinning out the tale about the dealer.
So why would she then get up and wander off to 'stretch her legs', as she claims? It does make sense that she'd go far enough to change her Snapchat account and message herself without Brianna seeing it. But Brianna and Boy Y had never met before and weren't speaking. She supposedly wanted to spend time with Brianna and didn't want her to leave early.
Why would you walk away to stretch your legs after you've walked to the bench already? She wouldn't genuinely need to stand up and get some exercise.
Boy Y's 'wee' excuse is much better.
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Overall I'm thinking now that X and Y were both there for the stabbing, and fully committed to it at the time. He did it (the physical strength and training), while she possibly told him when to begin, then stood back and watched (lack of any blood on her clothing).
Nothing else makes much sense. Her carrying Boy Y's knife in her pants for an hour doesn't make sense, especially if he treasured his knife so much.
Them messaging each other flirty and weird cat stuff and other jokes once they got home from a murder doesn't make sense if only one of them was involved, and the other was shocked and scared.
They were both in on it in their own ways -- her devious and dark, him pedantic and brutal -- until they realised the murder was attracting way more attention than they'd expected, and that they weren't going to get away with anything, and they blamed each other just like Thompson and Venables did.
In a sick way I would like to have it confirmed exactly what happened at the scene, but right now that's the only scenario that really seems plausible.
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Littered with chuckles and laughs. It was delivered absent of any emotion. It was cold.
This guy is contradicting himself as much as his client does. You can't complain that someone is laughing through their evidence, and that they're not showing any emotion.