Think about it. If you shoot at someone with 0% accuracy and you somehow hit them, then logically this statistic should increase.
Yes, there's no specification, so... what should the correct behavior be then? I think the idea of accuracy being less than the distance to the target is good, so you can't abuse it at short range. But then, it would still be easy to improve it if, for instance, you shot with 30% accuracy at someone 31 tiles away. So I think that another condition of accuracy being less than ~15% would be good.
Anyway, if you won't fix it, where should this bug be reported then?