The Swiss Federal Council and the Swiss Federal Assembly recommended that the initiative be rejected. The National Council opposed the initiative with 163 against 19 votes, the Council of States unanimously. All political parties in Switzerland with the exception of the Swiss People's Party and the Federal Democratic Union also opposed the initiative. The federal authorities argued that the initiative was vaguely phrased, making reference to the puberty of children, a developmental phase often difficult to exactly pinpoint in time and varying among children. They noted that the statute of limitations was necessary to prevent useless prosecutions, because after dozens of years the testimony of witnesses was often not reliable enough to secure a conviction. In the opinion of the federal authorities, imprescriptibility should remain reserved for crimes of exceptional gravity such as genocide and terrorist acts. Finally, the federal authorities argued that a previous change in law had already accomplished much of what the proponents desired, fixing the period of prescription at 15 years starting with the 18th birthday of the victim.