polkit.addRule(function(action, subject) {
    if ((action.id == "org.freedesktop.login1.reboot" ||
         action.id == "org.freedesktop.login1.power-off" ||
         action.id == "org.freedesktop.login1.suspend" ||
         action.id == "org.freedesktop.login1.hibernate") &&
        subject.isInGroup("wheel")) {
        return polkit.Result.YES;
    }
});