 The accused person has the burden of proving that he was unaware of the nature or contents of the subversive document that he made, caused to be made, was carrying or had in his possession or under his control; and that he made, caused to be made, was carrying or had the subversive document in his possession or under his control in such circumstances that at no time did he have reasonable cause to believe or suspect that the document was a subversive document.Part III of the CLPTA deals with illegal strikes and lock-outs in essential services.Section 5 of the Act defines a "strike" as "the cessation of work by a body of persons employed in any essential service acting in combination, or a concerted refusal or a refusal under a common understanding of a number of persons who are or who have been so employed to continue to work or to accept employment", and a "lock-out" as "the closing of a place of employment or the suspension of work, or the refusal by an employer to continue to employ any number of persons employed by him in consequence of a trade dispute, done with a view to compelling those persons, or to aid another employer in compelling persons employed by him, to accept terms or conditions of or affecting employment".