Do scientists lose professional credibility when they advocate for specific policies? Despite speculation that policy advocacy might have an impact on the perceived objectivity of scientists, a 2017 study published in Environmental Communication suggests otherwise. Using a randomized national survey, researchers found that, in most instances, participants' perception of a fictional climate expert didn't change after they were presented with examples of the expert advocating for specific policy changes.
Most advocacy messages we tested had no significant effect on Dr. Wilson’s credibility or general trust in climate scientists. Therefore, at a minimum, it is a mistake to assume that all normative statements made by scientists are detrimental to their credibility.
Kotcher, J. E., Myers, T. A., Vraga, E. K., Stenhouse, N., & Maibach, E. W. (2017). Does engagement in advocacy hurt the credibility of scientists? Results from a randomized national survey experiment. Environmental Communication, 11(3), 415–429. https://doi.org/10.1080/17524032.2016.1275736