Just for clarification, are you looking for evidence that the miners themselves.were violent, that they faced violence from the State, or a combination of both? In terms of evidence, there is far more evidence to support the fact that miners were attacked by the police/that police agitated things to the point of violence occurring. Remember of course, that while some could argue that miners created violent situations, the police were typically armed, and in instances like Orgreave, the police were on horseback and went in with an agenda of physically defeating the miners.