Over and over, Danforth says that the good have nothing to fear. What evidence can you give to show that the opposite is true?
I would say that one of the most striking elements of the play is that when individuals seize power without the public good at heart, everyone has something to fear. The reality is that Abigail's accusations sets in motion a frenzied state where "the best lack all passion while the worst are filled with passionate intensity." The governing body of Salem seems to be either gripped in fear or held by the forces of manipulation that seek to exercise power for their own benefit. In such a setting, it is not an issue of "good" or "bad" as much as it is one of utility. If individuals are not of use to those in the position of power, accusations and innuendo become accepted as evidence, while there is little in the way of institutional checks to stop such an abuse of power. In this scenario, those who are "good" have everything to fear because what is right and just are not the primary concerns of those in the position of power.
The evidence to go against this is pretty clear. You can see that the statement is not true simply by looking at some of the people who get convicted and executed.
We know that Tituba, at least, sort of "deserves" to be executed because she was really trying to mess around with the supernatural. But as far as we know, she's the only one who gets executed who actually did something.
By contrast, you have John Proctor executed (and Elizabeth would have been if she hadn't been pregnant). You have Rebecca Nurse and Giles Corey. None of them ever did anything wrong.
So their executions show that the good really do have something to fear.