According to this UK study, scientific misconduct is probably far more common than scientists are willing to admit or science fetishists are willing to believe:
The level and quality of research and training in scientific integrity has expanded in the last decades, raising awareness among scientists and the public. However, there is little evidence that researchers trained in recognizing and dealing with scientific misconduct have a lower propensity to commit it. Therefore, these trends might suggest that scientists are no less likely to commit misconduct or to report what they see their colleagues doing, but have become less likely to admit it for themselves….
A pooled weighted average of 1.97% (N = 7, 95%CI: 0.86–4.45) of scientists admitted to have fabricated, falsified or modified data or results at least once –a serious form of misconduct by any standard– and up to 33.7% admitted other questionable research practices. In surveys asking about the behaviour of colleagues, admission rates were 14.12% (N = 12, 95% CI: 9.91–19.72) for falsification, and up to 72% for other questionable research practices…. Considering that these surveys ask sensitive questions and have other limitations, it appears likely that this is a conservative estimate of the true prevalence of scientific misconduct.
I note that whenever the topic of scientific fraud or scientific credibility comes up, science defenders inevitably begin lecturing on how scientists are “trained” not to commit fraud and so forth. This is true, but they never seem to realize that the “we wuz trained” defense is no more credible for scientists than it is for journalists claiming that attending J-school somehow proves they cannot possibly be guilty of subjective bias. This paper should explode that oft-heard defense, while the sizeable gap between the 2 percent of scientists willing to admit their own serious misconduct and the 14 percent admitting they had witnessed others commit serious misconduct also tends to call the credibility of the average scientist into question.
And before any dimwitted science-fetishist brings up that old chestnut about how science critics shouldn’t use the products of scientists, let me remind everyone of two things. 1) Science is not engineering and most inventors and entrepeneurs are not scientists. 2) By this logic, no atheist critic of religion should be permitted to use the products of the religious faithful.