I think we all want to see the original research but the results - 2x as many deaths and 10x as many injuries - is not unexpected but the degree is pretty surprising (at least to me)
http://lawofficer.com/news/research-...-at-more-risk/
"He found that an officer working in a de-escalation agency, was twice as likely to be killed in the line of duty and 10 times more likely to be injured in the line of duty."