Which law did Gulliver wanted to be imposed on every traveller who wanted to publish his voyage?

From the text:

I could heartily wish a law was enacted, that every traveller, before he were permitted to publish his voyages, should be obliged to make oath before the Lord High Chancellor, that all he intended to print was absolutely true to the best of his knowledge; for then the world would no longer be deceived, as it usually is, while some writers, to make their works pass the better upon the public, impose the grossest falsities on the unwary reader.