There have been very few arrests in the  history of union violence in the new South Africa, and even fewer convictions.

The most glaring example was the 2006 strike by security guards, which saw at least 69 people murdered.    Most of them were beaten up before being thrown from moving trains. To date no one has been convicted of murder in connection with any of these deaths.

 As we pointed out during a protest earlier this year, strikes are routinely associated with intimidation.

We have seen bus drivers shot dead, teachers and pupils dragged from classrooms, and terrible things happen to hospital patients. All with little or no consequences for the perpetrators or those who seem to be their part-time leaders.

 Union bosses disown them when convenient but use the implicit threat of violence at whim.

The current conflict on some platinum mines is between the long-established  National Union of Mineworkers (NUM)  and the rival   Association of Mineworkers and Construction Union (AMCU), neither of whom has  clean hands.

Each party professes innocence.  AMCU vice-president Jeff Mthahmeme says the perpetrators belong to the   NUM, whose  general secretary, Frans Baleni, blames the newcomers.

Baleni also laments the inability of the police to exert control, saying the army should be called in.

We say this is still a police matter. The  officers who fell must not die in vain.

Their colleagues must decisively quell union violence. A new pattern must be established, where killers are punished.