Opponents such as Henry Kissinger, who himself was called to give testimony about the US Government's Operation Condor in a Spanish court, argue that universal jurisdiction is a breach of each state's sovereignty: all states being equal in sovereignty, as affirmed by the United Nations Charter, "idespread agreement that human rights violations and crimes against humanity must be prosecuted has hindered active consideration of the proper role of international courts. Universal jurisdiction risks creating universal tyranny – that of judges." According to Kissinger, as a logistical matter, since any number of states could set up such "universal jurisdiction" tribunals, the process could quickly degenerate into politically driven show trials to attempt to place a quasi-judicial stamp on a state's enemies or opponents.