Interesting :

"Kent State shootings: Does former informant hold the key to the May 4 mystery?"

http://www.cleveland.com/science/index.ssf/2010/12/kent_state_shootings_does_form.html

Curious too if is it now or was it in the past SOP for National Guard troops to be issued and permitted to carry 'hot' lethal ammunition loaded firearms when actively working riot control situations?