The public – and officials and experts - should be able to see the evidence behind policy decisions. Our latest Ipsos survey shows that two-thirds of people think it is important that government shows the public all the evidence used to make important policy decisions.

If we don’t know what government has looked at, we can’t follow the motivation for a policy, decide whether we agree with it, or judge whether it is working. Transparency prevents waste and avoids costly mistakes – only by seeing the evidence used can one part of government understand the intent of another or the insights of previous work.

The rules on publishing evidence already exist, but departments regularly ignore their own rules. What’s missing is the confidence among officials that ministers, and special advisors won’t turn on them for following these rules. The Prime Minister needs to give clear direction to all departments that they must show their workings for every policy: this will give civil servants the mandate and confidence they need to get on with sharing the evidence they have used in creating a policy.

We need your help to put the pro-evidence, pro-transparency voice where it matters.

Following the Budget, we expect to see a flurry of policy announcements, with the Labour government having announced 40 new bills in the King’s Speech, we need to be ready to publicly score them for whether government has properly shared the evidence base behind decisions before MPs are expected to vote on them, or the public expected to accept them. When parties have an insurmountable majority, government can assume its legislation will go through parliament unopposed. But proper scrutiny of legislation by parliament is vital for wider society to follow, implement, trust and, if necessary, sound the alarm on changes that may dramatically affect the lives of millions of people. That means MPs on both sides of the House must look at the rationale and evidence behind proposals, not just vote bills through on party lines. Fundamental questioning of a bill – how do we know the policy will do what is intended? – needs to be done by the elected members in the commons, and this is only possible if MPs can see the same data and analysis as ministers and civil servants.

£10,000 will enable us to put major policies under the spotlight as they are announced.