The Autumn Statement released yesterday showed exactly why we need 'Red Books for Evidence'. The Autumn Statement is of course inherently political. And yesterday was no different. George Osborne's statement had a clear political narrative to help "working people" and where this government would like to take the country. There are many arguments about whether he is politically right or wrong.

But there may be fewer arguments over whether there is evidence behind some of these decisions. The spending decisions taken in the Autumn Statement are just a click away. This meant that as soon as he had sat down, it was widely reported and tweeted that the reduction in borrowing came from one source - the £3.5 billion to be raised from the sale of the 4G spectrum. Whether or not this is the correct use of the fund is another debate, but we did not have to delve into the complex Autumn Statement to work this out. Indeed, as a separate webpage, it was extremely easy to see. For the Autumn Statement and Annual Budget, the behind the scenes 'working outs' are right alongside them ready for interrogation and debate.

The question we are asking at Nesta is why can't this be replicated across all government departments so we know exactly what evidence was used for each policy decision? This should not just be for spending, indeed we know some of this from the Budget, but we should also be able the see the evidence behind decisions taken on education, healthcare and crime. Imagine if we could see the evidence behind these decisions in a simple table. If the Government want tougher knife crime laws, we could see clearly and simply the evidence why they believe the policy decision will work.

One of the announcements in the Autumn Statement could be an interesting test case for a 'Red Book for Evidence'. The welfare uprating bill will be a multi-year settlement for welfare expenditure. How high or low welfare payments should be is an important debate to have in an age of austerity. It would be a great opportunity for government departments to show exactly why policy decisions have been taken. There will be huge debate over this Bill and the perceived impacts it will have on society. Yet with the evidence behind it clear, all sides would be able to react and debate it with the Government's decision making process clearly shown. In essence, showing an 'evidence audit trail', demonstrating what evidence has been considered, and by extension, what has been ignored.

In today's age when all data is just a click away, and the Government are promising that more data will be available, the battle for data is slowly being won. Government data that was once locked away, hidden from view is now open for all to see. Few would now argue for it to go back to the cupboard. But can we now take this a step further? Can we not just open up datasets but also open up the policy making process? How can policy makers more clearly show their 'workings out', to provide a clear audit trail for evidence to accompany the policy decisions made?

Politics - and therefore policy making - may always be ideologically driven. And we may always continue to have disagreements about how 'good evidence' is defined, the sources used, or the conclusions reached, but at least with Red Books for Evidence we could have these discussions with the information in front of us.

Will you join us to make Red Books for Evidence a reality?