Before Henry's reign, the church, with the pope's backing, had become more powerful and asserted more authority. Henry tried to return to the concept of the king being appointed by God and as the head of the church as well as of the state, as in Henry I's time, and to include the church in his reform of the legal system, which would make the spiritual jurisdiction and temporal jurisdiction conform to a common justice. Toward this end, he published the Constitutions of Clarendon. But the Archbishop of Canterbury, Thomas Becket, refused to agree to them, although as Chancellor he had seen the beneficial effects on the kingdom of Henry's legal measures. The disagreement came to a head in Henry's attempt to establish the principle of "one law to all" by having church clerics punished by the civil courts as before, instead of having "benefit of clergy" to be tried and punished only in ecclesiastical courts, even for secular crimes. Clerics composed about one-sixth the population. The church courts had characteristically punished with spiritual penalties of a fine or a penance, and at most defrocking. It could not impose a death penalty, even for murder. When Archbishop Becket was murdered and became a martyr, "benefit of clergy" became a standard right, except for offenses in the king's forests. Appeals could be made to the pope without the king's permission. The king could take a criminal cleric's chattels, but not his life. However, though theoretically bishops were elected by the body of bishops with the approval of the king, as a practical matter, the king chose the bishops and the abbots. It was a constant matter of dispute, in which the pope would sometimes involve himself. Selection of archbishops was also a frequent matter of contention between king and pope. The church copied the assize procedure developed by the Royal Court to detect ecclesiastical offenses though it retained trial by compurgation. Bishops could request the Chancery to imprison an offender who had remained excommunicant for forty days, until he made amends. Chancery complied as a matter of course. This went on for six centuries. The delineations of jurisdiction among these courts were confused and there was much competing and overlapping of jurisdictions. However, the court could appoint arbitrators or suggest to the parties to compromise to avoid the harshness of a decisive judgment which might drive the losing party to violent self-help.