There's good reason not to trust scientists sometimes. It carries over to "science" depending on how you define it. In the purist sense, there should be no doubt that the idea of science is trustworthy. On the other hand, the actual practice of science is carried out by people, who are not. So if you define "science" as the actual societal interactions that emerge from the purist ideal of "science", it's not always trustworthy or well-meaning. It can often used be used as a marketing tool in medicine. In other cases, it may be well-meaning, but negligent.
http://www.theatlantic.com/magazine/archive/2010/11/lies-damned-lies-and-medical-science/8269/
Of course, I think most scientists that advocate for science actually intend the purist definition: what science is supposed to be about; but a subculture are laymen or more likely to think of the science culture when they say "science", not the ideal of empirical evidence backing up claims.