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Statutes passed by the Northern States to protect the negroes within their borders. The first acts were passed about 1840, though Indiana and Connecticut had previously provided that fugitives might have a trial by jury. After the Prigg decision, many of the States passed Acts prohibiting the use of State jails in fugitive slave cases. The Fugitive Slave Law of 1850 aroused the most violent opposition in the North, and before 1856 many of the States had passed personal liberty acts. Beside prohibiting the use of State jails, these laws forbade State judges and officers to assist claimants or issue writs. Trial was to be given all alleged fugitives. Heavy penalties were provided for the violation of these laws. Such acts were passed in Vermont, Connecticut, Rhode Island, Massachusetts, Michigan, Maine, Wisconsin, Kansas, Ohio and Pennsylvania. Of the Northern States, New Jersey and California alone sanctioned the rendition of fugitives.