What is the ‘hot-tubbing’ of medical experts?

What is the ‘hot-tubbing’ of medical experts?
Hot-tubbing is a term used when concurrent evidence of expert witnesses is heard by the court. It can be used in criminal, civil, and coronial court systems. There are said to be many benefits to utilising a hot-tubbing practice, including that it can be an efficient and focused way of adducing expert evidence. There is a risk, however, of cognitive bias and the phenomenon of ‘group think’ occurring.