A lawyer's surprised police aren't taking investigations further, following the death of a Palmerston North teen playing a 'Run it Straight' game.

19-year-old Ryan Satterthwaite suffered a serious brain injury on Sunday participating in the sport - and died in hospital on Monday. 

The tackling competition is big on social media.

Lawyer Matt Goodwin says most people participating would know there's a serious risk of injury, even death.

"So in assuming that risk, I think the question is whether it's something that's acceptable."

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