The rule that prisoners had to be belted in the van was in effect for about a week when this happened. The incognito friend of one of the officers said that the reason they will not belt an irate prisoner in is they are afraid of being bitten when they reach across to fasten the belt.
On another note, the "severed spinal cord" quote is from the family attorney - not the ME. The news media kept repeating what the family attorney said.