The numbers don't lie.
There is only 6% of conservatives in the science field.
The college's will not hire equal amounts of college professor's, who are conservative as well as liberal.
Some liberal college's will not allow conservative view points to be heard. Or guest speakers.
So in your opinion when the department head of a particular science at a university is interviewing candidates for a professor job, the head asks him/her about her political idealogy?
That's quite a conspiracy theory.