In a controversial move, the British government decided recently to set up a people’s panel of 5,000 voters to test public reaction to its policies.
In the sense that’s being used here — of a group of people brought together to take part in a discussion, or to advise or judge on a proposal — the word panel goes back at least to the eighteenth century. But in its word origin it’s no more than a small pane, a meaning which we still employ when we speak, say, of one of the sections of a door. When it first came into the language in the fourteenth century, from the Latin pannus (a piece of cloth), the Latin sense came over intact so that it referred exclusively to cloth (the word counterpane is the only survival of this connotation in modern English, though that word was created in the fifteenth century from the older and correct term counterpoint through false etymology).
We got from cloth to people by a series of steps. Firstly, it started to be used of a small piece of anything, not just cloth. In particular, it was applied to the scrap of parchment on which the sheriff (as royal representative in the shire) wrote the list of jurors who were to try a case (and which he usually attached to the writ calling the trial). Eventually, by a process of transfer of meaning, panel came to be used of the jury itself, and also generated the verb empanel, as in to empanel a jury.
Later still, the more general sense grew up that we still use. In a way this was a partial return to an older function of a jury, which was originally conceived as a group of knowledgeable local people who were to give evidence rather than decide the guilt of the accused. In the way the Government is now using it, it is almost equivalent to that very modern term focus group beloved of market researchers and, more recently, the Labour Party itself.