One of the elements that several of these plays have had in common is the use of verbatim material. In the National Theatre's case testimonies were gathered through extensive interviews. For the production of Brexit: The Musical, the politician's own words were warped into song.
Verbatim theatre is a development of Documentary Theatre, and is considered to have been influenced by Joan Littlewood's work during the forties, fifties and sixties. It is a useful tool for dramatists when working on political, sociological or State-Of-The-Nation plays as it allows for a range of views to be expressed and presented in myriad ways.
I feel that one of the ways in which theatre can create response in audiences is through empathy: audiences identify with one or more of the characters and undergo catharsis or emotional development through that character's journey. Verbatim theatre allows for this to happen in a truthful way rather than in one that has been entirely artificially constructed.
Through the use of direct testimony, writers can combine artistic licence to create impact: if a verbatim play were simply reconstructions of conversations or statements, we may as well watch the news! It is this interweaving of reality and fiction that makes a verbatim play truthful, in a way that news reports and documentaries simply can't match (I also suspect this is why so many historical documentaries use reconstructions and actors - if we can't see or hear "something", how can we be expected to "see" or "hear" something?
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Yes, personal bias will come in to play; that of the playwright, the director, the actors and each member of every audience. The message I took from My Country may not be the same as the person sat next to me. But this is a risk with every play. Many theatres, when confronted with crisis rummage in the archives and produce a Shakespeare in modern dress, which is then hailed as a sign of our times. It is something quite brave and radical to actually use contemporary, relevant voices to make a point.
Theatre is also a rather 'safe-space' for pitching ideas that may be shouted down in regular conversation: the conventions of theatre dictate that the audience is most often a passive spectator, watching and hearing the action unfold. This allows for the playwright to pose an argument in an eloquent and measured way, and to occasionally present the opposing point, without being interrupted, or shouted down.
In a time when no one gives the other a chance to speak, and refuses to hear anything that contradicts their previously confirmed point of view, it is more essential than ever that theatre gives voice to those who are silent or silenced.
It's no surprise to me that the Ancient Greeks were the ones who created both democracy and theatre festivals, and that engagement with both was considered to be an essential aspect of a citizen's civil duty. I think it should be again.