It's always been a complicated relationship. Politicians rely on scientists to provide them with accurate advice they can use to make important decisions about the lives we all lead. But keeping politicians up to date with science, as parliament's scientific champion Andrew Miller admits, is "permanently difficult". And ministers often decide to ignore the advice they receive altogether.
Each department has a chief scientific officer. Miller, as chair of the Commons' science and technology committee, talks to all of them. "With a few exceptions, the relationships are moving in the right direction," he says. "There have been some exceptions where the way in which scientific advice has been sought and delivered has been tantamount to saying, 'here's the answer, now give me the question'. That comes from people who don't understand how proper scientific decisions are determined."
Politics is often to blame for the disconnect between science and policy. Take fracking, one of the most controversial new ideas to emerge in this parliament. The arguments against extracting shale gas were all about earthquakes for a long time, even though the risks of a serious tremor are minimal. "I stepped in and got a few people from the Geological Society to start talking about more accurate perception of the capabilities and the engineering involved," Miller says. "Which has helped." Now the most powerful arguments against fracking are about climate change.
The chief villain pointed out by Miller is Owen Paterson, the environment secretary, whose use of science in the badger cull debate has been highly questionable. "As much as I am a supporter of the anti-cull side of the argument, I don't try and argue that is the science says so. The science is unfortunately very equivocal.
"If you look on Owen Paterson's website, he claims he's an expert on bovine TB. He is not. He can rabbit on about it but he can't answer the scientific challenge because there isn't a direct answer. The direct answer is there's a lot more questions."
Miller remembers a press conference in which Paterson put public pressure on Defra's chief scientist Professor Ian Boyd. The environment secretary put Boyd "in an impossible position by spouting off about the badger cull and the turning to Ian for him to make a comment", Miller complains. What he should have done was give Boyd "the freedom to say 'I've given the minister the policy options, based upon the science that's there and the decision is a policy one the minister must make'."
Not all ministers are bad at this. Previous home secretaries have got into a lot of trouble with scientists – think of David Nutt's rows with New Labour home secretaries over drugs policy. But the current holder of the job, Theresa May, actually gets a lot of praise from Miller over her handling of the decision to ban khat.
May's decision was subsequently slammed by MPs for not being based on evidence of medical or social harm. But Miller doesn't mind because she avoided trying to use scientific advice to back up her decision. "She wrote a brilliant letter to the advisory committee on misuse of drugs – that was exactly the way a minister should behave.
"She set out in that letter her thinking, saying thanks for the scientific advice she's received. Then she goes on to say… why she is not acting on the scientific advice.
"The scientific advice is about the health to you as a user. So Theresa's rejection is based upon two factors: the perceived behaviour in populations where the use of khat is prevalent, and a judgement on international relationships because a number of our key partners are a little bit pissed off that we allow khat to be freely transported around."
Miller's own job, trying his hardest to promote science and scientific thinking to MPs, has had a tortuous evolution. Government departments didn't have chief scientists until the first one appointed in Harold Wilson's government. And it wasn't until the 1980s that a group of MPs went to Margaret Thatcher and asked her for cash to set up an Office of Science and Technology. She said there wasn't any cash available, so the MPs went elsewhere and raised the money.
The result, the Parliamentary Office of Science and Technology, was brought in-house in the early 90s. Now, young post-docs taken from their speciality work via three-month secondments produce research work for MPs, keeping them informed as best as they can with peer-reviewed work.
"Sometimes people are a tad surprised at the degree of understanding. Nevertheless, there are weaknesses." He points to the number of MPs who were guilty of "pandering to the nonsense that Andrew Wakefield produced" warning about the dangers of the MMR jab. "Parliament very nearly went into an anti-MMR vein, which would have been a disaster.
"We see this regularly. We're seeing it now – the debate on GM foods, badgers, nuclear power, fracking, on managing floods, you name it – there are some interesting interpretations of what is achievable by science. Because even though there is a lot happening here in our system, way beyond that available to our colleagues in other countries, it's not enough."
The international reference is significant. Miller might be worried about the levels of understand here, but at least we're not as bad as the US. "About ten per cent of the House have at some stage in their career worked in a stem discipline. Now that may not be huge, but I used to tease my American friends by saying that's ten per cent more than they have. Their figures have moved up in the right direction by one… when they elected their first ever particle physicist."
Miller blames coalition governments for producing a "particularly weak" crop of ministers and even goes so far as to recommend some basic lessons in scientific methodology for new arrivals in government departments. Most strikingly of all, though, he thinks it's MPs who need educating the most. "There is a greater need than there ever was for a more scientifically literate group of policymakers," he warns. While he spends most of his time criticising the politicians, he has a message for scientists too.
"Make it part of your job to go and knock on the door of your own MP and explain to them the importance of the research you're undertaking," he tells them. MPs will be happy to take the time to listen, he assures them. "Compared to most of our surgeries, a bit of science would be a breath of fresh air."