Kenneth P. Green and Hiwa Alaghebandian think they have identified why Americans seem to have less regard for science–and scientists–than they used to.

Our theory is that science is not losing its credibility because people no longer like or believe in the idea of scientific discovery, but because science has taken on an authoritarian tone, and has let itself be co-opted by pressure groups who want the government to force people to change their behavior.
In the past, scientists were generally neutral on questions of what to do. Instead, they just told people what they found, such as “we have discovered that smoking vastly increases your risk of lung cancer” or “we have discovered that some people will have adverse health effects from consuming high levels of salt.” Or “we have found that obesity increases your risk of coronary heart disease.” Those were simply neutral observations that people could find empowering, useful, interesting, etc., but did not place demands on them. In fact, this kind of objectivity was the entire basis for trusting scientific claims.

But then they started telling us what we had to do.

So, objective statements about smoking risk morphed into statements like “science tells us we must end the use of tobacco products.” A finding of elevated risk of stroke from excess salt ingestion leads to: “The science tells us we must cut salt consumption in half by 2030.” Findings that obesity carries health risks lead to a “war on obesity.” And yes, a finding that we may be causing the climate to change morphed into “the science says we must radically restructure our economy and way of life to cut greenhouse gas emissions radically by 2050.”

As Green and Alaghebandian put it, this “authoritarian” turn doesn’t sit well with Americans. They wondered when it all started and did a search on “authoritarian” sounding phrases in science stories.

[A]round the end of the 1980s, science (at least science reporting) took on a distinctly authoritarian tone. Whether because of funding availability or a desire by some senior academics for greater relevance, or just the spread of activism through the university, scientists stopped speaking objectively and started telling people what to do. And people don’t take well to that, particularly when they’re unable to evaluate the information that supposedly requires them to give up their SUV, their celebratory cigar, or their chicken nuggets.
The public’s trust is further undermined by scientific scandals, such as the recent ClimateGate affair, when it became apparent that climate scientists, if not overtly cooking their books, were behaving as partisans out to create a unified perception of the climate in order to advance a policy agenda. The climate community is probably the biggest user of the authoritarian voice, with frequent pronouncements that “the science says we must limit atmospheric carbon dioxide concentrations to 350 parts per million,” or some dire outcome will eventuate. Friends of the Earth writes, “For example, science tells us we must reduce our global greenhouse gas emissions to prevent dangerous climate change.” America’s climate change negotiator in Copenhagen is quoted by World Wildlife Fund as saying, “China must do significantly more if we are to have a chance to solve the problem and to arrive at an international agreement that achieves what science tells us we must.” Science as dictator—not a pretty sight.

So go back to objectivity in reporting your findings. Less advocacy, more science.