Two incidents recently in Australia about bystander restraint causing death/injury.
http://www.dailytelegraph.com.au/news/nsw/citizens-arrest-man-critical-after-being-detained-over-alleged-shoplifting-in-central-coast-store/news-story/0569deb52f985889132b2bea0b4a217a
Related are the other recent restraint deaths by police in the US. Controversy around excited delerium and positional asphyxia in restraints.
Certainly sympathomimetics and obesity are risk factors.
