The Jersey police are going to have a tough time. All sorts of problems would face a forensic archaeologist investigating a case like this, and the key issue they have got is one of dating. There are scientific and contextual ways of dating bones and, while both can be helpful, it will be hard to say anything with great certainty.

An archaeologist would use radiocarbon dating but that only works for very old bones. There is no point doing it for bones from the 20th century – although, thanks to nuclear-weapons testing, you can see a radiocarbon peak in bones from the 1950s onwards.

There are methods, such as polonium or lead dating, which can narrow the timescale. These elements have relatively short half-lives compared with radiocarbon, which means they decay faster and so could refine a date more usefully in forensic terms. That assumes you have got reasonable amounts of bone to work with, which in this case they do not have.

The other way of dating bones is from their context. The ground, particularly around buildings, is full of layers, and this allows bones to be dated relative to where in the sub-surface they were found. If they are under the foundations, they will predate the building above it. Or the bones could be incorporated within layers introduced from somewhere else, or sealed underneath a more modern surface.

The Jersey police have archeologists there and this is something they will be looking at. However, the dates you draw from this are bound to be broad. And if bones are just lying on the ground, then in a way they are out of time and space.

Again, the more bones you have, the more certain you can be. If you find a complete skeleton, you can be reasonably sure that was where it was buried. With fragments, it is possible that they could have come from elsewhere quite accidentally, as rubble or soil is moved about.

One difficulty they probably will not have to contend with is decay. This can be a problem in acidic soil, when bones can demineralise and even vanish completely. In a dry, rubbly cellar, however, they should survive reasonably well.

- Professor John Hunter specialises in forensic archaeology at the University of Birmingham

Times Recommends

• Bank charges hit us for being human
• Sorry, Father, thou still shalt not steal
• The shed where Santa’s failures go to die