Railtus posted:

Good question. I have never seen any official work addressing that subject, although it seems plausible that it was just never kept track of to a sufficient degree to cause an issue. Once you know Church X has a finger-bone of a saint, you probably do not have much incentive to start tracking down the number of other churches which had other finger bones, you just want to go to that church for pilgrimage.

Basically the research needed for a medieval person to notice, cross referencing various relics in what churches, would be very demanding and time consuming. I think honestly few people were willing to make the investment needed to do the research. Also it was not too common to claim to have the whole skull of a saint, if you just have a piece of it that counts and it avoids those problems in the first place.

However, it was known that not all relics were genuine. For example, in the Canterbury Tales Chaucer describes the Pardoner as selling fake relics, so the concept was generally recognised. The church also made a point of forbidding the selling of relics on occasion, which is a sign it probably happened.

So the short answer is they didn’t deal with it. :P I think the church could have made a wide census tracking down exactly what relics were where and which ones were genuine etc. But it seems no one wanted to do it.