This article first published in Third Sector.

Why is so little policy based on sound evidence? Many voluntary organisations, academics and others spend time producing research in order to influence the government. There are some successes – but much policy appears to disregard the evidence.

Mark Henderson is head of communications at the UK’s largest charitable funder, the Wellcome Trust, and author of The Geek Manifesto, which calls for a more scientific approach to policy and politics. He says there’s little political price to be paid when MPs ignore the evidence. He also says that, in their constituencies, most MPs know the business people – who, after all, will ensure that people of influence have the benefit of their views – but rarely know the scientists. They probably don’t know the charity sector people either.

I am an advocate of evidence and hence often in meetings about the importance of getting evidence into policy with organisations such as the Alliance for Useful Evidence, the Institute for Government, the Hewlett Foundation or the National Institute for Health and Care Excellence. If Henderson is right, we’re all stuck in an echo chamber and missing a trick.

So I went to see my MP. And with haste: she is Justine Greening, a Cabinet minister – for international development, as it happens – and the recent reshuffle was looming.

“Hello, I’d like to talk about how keen I am that government policy be based on robust evidence,” I said. An unusual opening in an MP’s surgery, to say the least. But it led to a spirited conversation. Before my visit, I had, by way of a focus group, asked on Facebook what I should raise with her. The doctors all rattled on about distinguishing between good and bad evidence, and everybody cited weariness of politicians cherry-picking data that suit them. Having removed the names, I printed out the responses and presented them to her.

Most revealing were two interconnected things. First, when I told Greening that the Department for International Development was generally very sophisticated in its use of evidence, she seemed amazed. “Most of my constituents think foreign aid is a waste of money,” she said. Actually, plenty of her constituents don’t think that – I socialise with them and they say so – but, clearly, those views had never reached her.

If we want MPs to act on evidence, we should go and tell them that that’s what we want

Second, not a single person I know has ever been to see their MP. Many of us battle attitudes in what we might call “the uncharitable press” and we bemoan MPs who pander to it. MPs hear and heed calls to continue the Work Programme, to cut the Third Sector Research Centre and so on. If we’ve never told them our contrasting views, we’ve nobody to blame but ourselves.

So go and see your MP – it’s your democratic privilege and weirdly empowering.

Does it make any difference? I don’t know. Perhaps we should gather evidence on this. Ben Goldacre, the broadcaster and science campaigner, and the innovation charity Nesta created an online tool, RandomiseMe, which enables anybody to run a randomised, controlled trial. We could all participate in such a trial: half of us go to see our MPs and half don’t, and we watch for subsequent differences in their voting behaviour. If we want MPs to act on evidence, we should go and tell them that that’s what we want.

What IS good evidence? Not this–>