That is true for basicly everything humans ever touched. Humans are just not perfect, so you have to look at their personal intrest. Fortunatly science tends to attract a fairly large group of people actually intressted in studying the subject and not too much about personal gain. That is combined with a culture of testing ideas, which make faking more difficult, but not impossible. What I want to say is that science tends to be among the most accurate systems we have, certainly better then politicans or capitalists.