Every new technology has its Luddite detractors, while every rich corporation can bribe people with impressive-sounding credentials that claim product safety. Neither description fits the participants in the controversy over wireless safety. Y2K. Likewise, the medical experts who reassure us aren't comparable to the industry stooges that deny the dangers of passive smoking or global warming. There is a genuine scientific controversy, reaching right to the heart of what constitutes evidence. Science is supposed to progress through educated trial and error.
Someone thinks up a theory, then someone else tests it with experiments.
Details of experiments are published in peer-reviewed journals, so that other scientists can check the results. When several teams all see a similar outcome, the experiment is considered replicated and a theory becomes accepted. If they get different results from those predicted, the theory is said to be falsified and abandoned. A theory like gravity or evolution is fairly easy to confirm, using weights or bacteria cultures. Likewise, anyone with a few thousand dollars worth of equipment can falsify the theory of cold fusion.