Statutory authority is a complete defence and act of God or act of a third party may provide a defence in certain situations.

制定法授权是相对于私人妨害侵权的一个完全的抗辩，自然力作用和第三人行为在相称的情况下也可能构成抗辩。

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They have a statutory defence and that is they have to be seen to carry out a reasonable system of inspection and maintenance.

BBC: Stoke & Staffordshire

But Mr Straw said he "could not see much difference" in the idea of replacing the common law defence of "justification" with the statutory defence of "truth".

BBC: Falconer: Libel plans are 'impressive' and 'worthwhile'