Whether international human rights treaties constrain the behavior of governments is a hotly contested issue that has drawn much scholarly attention. The possibility to derogate from some, but not all, of the rights enshrined in the International Covenant on Civil and Political Rights (ICCPR) during declared and officially notified states of emergency provides a hitherto unexplored test case. If governments were increasingly violating non-derogable rights during derogation periods then this provides evidence that the ICCPR has no sufficient constraining effect on state parties. I analyze whether specific individual human rights as well as two aggregate rights measures are systematically more violated during derogation periods in a global sample over the period 1981 to 2008. I find that regime type matters: autocracies step up violation of both non-derogable and derogable rights, anocracies increasingly violate some derogable and some non-derogable rights, whereas democracies see no statistically significant change in their human rights behavior during derogation periods. This result suggests that the main general international human rights treaty fails to achieve its objective of shielding certain rights from derogation where, as in autocracies and anocracies, a constraining effect would be needed most.