That's the best you can do though. Politics is only one way to slice the problem. People can act maliciously for lots of other reasons you may not know about or expect, up to the totally random "this person was trustworthy until they got paid $$$$ to not be".
Depending on the project, that can be a very naïve view. See https://en.m.wikipedia.org/wiki/Underhanded_C_Contest