The struggle of the kings against the seigniorial elements of Aragon and Valencia (in furtherance of their policy of absolutism and centralization) has already been traced up to the point where royalty gained the upper hand in the reign of Pedro IV. One result of Pedro’s victory was the reduction of the power of the _Justicia_, no longer a creature of the nobility (to mediate between them and the king) but a royal appointee, exercising strictly judicial powers as chief justice of the realm. Even in this respect his authority was limited by the founding of a tribunal to accompany the king. Attempts continued to be made to establish the independence of the _Justicia_, and the _Cortes_ declared him irremovable, but the kings compelled their appointees to give them a letter of resignation, with the date left blank, or disregarded the prohibition of the _Cortes_ altogether, deposing a _Justicia_ if it suited them to do so. Pedro IV enacted that no person of higher rank than that of _caballero_ should be governor in Aragon, thus removing another factor which had formerly contributed to civil strife. Aside from the abolition of the Privilege of the Union and the reforms just mentioned (together with others of lesser note), the kings did not modify the political organization of Aragon, but became in fact the principal element in the state, working their will even to the point of acts at variance with the laws. Great diversity in charter rights and jurisdictions continued to exist, although a number of general compilations of legislation like those in Castile were made. These became supplements to the already-mentioned code of Jaime I.[47] Other volumes were prepared of the customs of the realm, and the agreements of the _Cortes_ were also an important legislative source. The abolition of torture and of the vulgar proofs may be mentioned among the reforms in judicial procedure. The nobles remained almost wholly exempt from taxation, even with respect to the lands which they might acquire in royal territory. [Sidenote: Relations of church and state in Aragon.] [Sidenote: Benedict XIII.]