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This case ([1988] 1 WLR 394) is a good example of the principle of Ejusdem generis being applied wrongly, and against precendent, presumably in order that the intention of the legislature could be given effect. It concerns whether or not an electric 'stun gun' is prohibited by the Firearms Acts. Clearly such a device is not a firearm in the usual sense, but the Acts do prohibit devices that discharge any noxious liquid, gas or other thing, and are clearly framed to restrict the ownership of weapons that have no justifiable use outside the military forces. Clearly, application of ejusdem generis according to precedent (e.g., Evan v cross (1938)) would say that electricity is not ejusdem generis with noxious gasses and liquids, and therefore not caught by that clause in the legislation. The House of lords, however, differently, holding that, in effect, electricity was a 'noxious thing'.

Clearly there are good public policy reasons for restricting the ownership of devices that can discharge tens of thousands of volts across someone's flesh, which may account for why it was deemed necessary to modify the application of an important interpretative tradition. The issue of whether electricity is ejusdem generis with noxious liquids or gasses was raised again in a similar case (R v Muongo [1996] CLY 1497) which concerned an electric anti-theft device fitted to a briefcase. However, the court in this case decided that a briefcase is not a 'weapon' at all, the result in Flack v Baldry, whatever its merits or otherwise, was not relevant.