Of the spectrum of all possible policy options the frame of all reasonable options is called the ‘Overton Window‘. It is named after its originator, Joseph P. Overton, former vice president of the Mackinac Center for Public Policy
By reasonable its means those considered reasonable in terms of the current political discourse, rather than the additional test of being reasonable in terms of practicality etc.
It is a means of visualizing which ideas define that range of acceptance. Proponents of policies outside the window seek to persuade or educate the public so that the window either “moves” or expands to encompass them. Opponents of current policies, or similar ones currently within the window, likewise seek to convince people that these should be considered unacceptable.
After Overton’s death the concept caused a lot of chatter amongst thinks tanks, expanding the idea so that new ideas entering the public discourse they can shift the window of what is considered reasonable. add the concept of moving the window, such as deliberately promoting ideas even less acceptable than the previous “outer fringe” ideas, with the intention of making the current fringe ideas acceptable by comparison.
Lets take an example. A political party proposes education vouchers, this is condemned, but following public arguments a new ‘compromise plan is put forward which may be considered reasonable, whereas if this watered down plan had been put forward originally it may have at first been considered extreme.
The following diagram sums it up.
The technique has been used by many previously fringe think tanks to make their ideas seem mainstream. A classic example is the very anti-planning discourse used by the Policy Exchange (see numerous posts here exposing there methods). The term has even been taken up by that way-out king of conspiracy theories Glenn Beck as the Title of a dreaful novel.
It is a form of door in your face negotiation. ‘Would you donate £5,000 to our organisation? No ok how about £5’
The onslaught of essays, breakfast briefings and speeches by those, including those in No10, proposing an abolsute minimalist and anti-planning approach in the new NPPF is a classic example. At the end of the day the planning system might not be watered down as such extreme thinkers want but it might have been watered down considerably.
The problem is that even giving credence to offbeam ideas can give them a false credence. This is known as “Okrent’s Law” during his tenure asa news paper editor Okrents commented about his job “The pursuit of balance can create imbalance because sometimes something is true,” referring to the phenomenon of the press providing legitimacy to fringe or viewpoints in an effort to appear even-handed. Classic examples is undue press given to climate change deniers and opponents to evolution.
“Some would say that hydrogen cyanide is a delicious and necessary part of the human diet, but others claim it is a toxic and dangerous substance. The truth must therefore be somewhere in between
So if you see someone trying to create an Overton Window there can be only one rational response, don’t compromise.