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In 1754 Parliament, at the petition of Shirley, then Governor of Massachusetts, passed an act providing for a more thorough enforcement of the navigation and revenue laws. General warrants were to be issued by the courts to revenue officers to continue for an indefinite period, and not returnable into the court, for the seizure and examination of goods imported by illicit traders. These were called writs of assistance. They were legalized by the Townshend Acts of 1767. The colonists vehemently objected to them, because their vague and general terms left the way open to great abuses against the liberty of the subjects, in the search of premises. In February, 1761, arguing against an application for such writs before the Superior Court of Massachusetts, James Otis declared the navigation laws illegal, and denied the claim of Parliament to legislate for the colonies.