translate English to French: On the basis of this evidence, the Board -- and later the Umpire -- agreed that there was some danger of violent action and concluded that "they did not participate" in the labour dispute.
Sur la foi de ces éléments de preuve, le conseil -- puis le juge-arbitre -- a convenu qu'il y a eu un certain danger de violence et a conclu "qu'ils n'ont pas participé" au conflit collectif.