On students
Since the modern conservative movement in the United States began in the mid-20th century, conservative authors have argued that college students are unduly influenced or indoctrinated as a result of the prevalence of liberal faculty at their schools. William F. Buckley's God and Man at Yale: The Superstitions of "Academic Freedom", Allan Bloom's The Closing of the American Mind, Dinesh D'Souza's Illiberal Education, and Roger Kimball's Tenured Radicals have made such arguments. George Yancey argues that there is little evidence that the political orientation of faculty members affects the political attitudes of their students. A study by Mack D. Mariani and Gordon J. Hewitt published in 2008 examined ideological changes in college students between their first and senior years and found that these changes correlated with that of most Americans between the ages of 18 and 24 during the same time period, and there was no evidence that faculty ideology was "associated with changes in students' ideological orientation" and concluded that students at more liberal schools "were not statistically more likely to move to the left" than students at other institutions. Similarly, Stanley Rothman, April Kelly-Woessner, and Mathew Wossner found in 2010 that students' "aggregate attitudes do not appear to vary much between their first and final years," and wrote that this "raises some questions about charges that campuses politically indoctrinate students." Analysis of a survey of students' political attitudes by M. Kent Jennings and Laura Stoker found that the tendency of college graduates to be more liberal is largely due to "the fact that more liberal students are more likely to go to college in the first place."
On faculty
Rothman, Kelly-Woessner, and Woessner also found in 2010 that 33% of conservative faculty say they are "very satisfied" with their careers, while 24% of liberal faculty say so. Over 90% of Republican-voting professors said that they would still become professors if they could do it all over again. The authors concluded that, although such numbers are not definitive as to how faculty members feel that they have been treated, they provide some evidence against the idea that conservative faculty members are systematically discriminated against. Woessner and Kelly-Woessner also examined what might have given rise to the differences in the numbers of liberals and conservatives. They looked at the choices made by undergraduate students when planning future careers. They found that there were no differences in intellectual ability between conservative and liberal students, but that liberal students were significantly more likely to choose to pursue PhD degrees and academic careers, whereas conservative students of identical academic accomplishments were more likely to pursue business careers. They concluded that the greater numbers of liberal than conservative professors could be accounted for by self-selection in career paths, rather than by bias in hiring or promotion.
Lawrence Summers said at a symposium about The Social and Political Views of American Professors that he considers it a problem that some academics express an "extreme hostility" to conservative opinions. He observed that faculty who were invited to give Tanner Lectures on Human Values were almost always liberals, and expressed concern that an imbalance in political representation at universities could impede rigorous examination of issues. He also attributed the small numbers of conservative professors largely to the career choices made by people comparing academic careers with other options.
One outcome of these controversies was the founding of the Heterodox Academy in 2015, a bipartisan organization of professors seeking to increase the acceptance of diverse political viewpoints in academic discourse. As of February 2018, over 1500 college professors had joined Heterodox Academy. The group publishes a ranking which rates the top 150 universities in the United States based on their commitment to diversity of viewpoint.
Jon Shields and Joshua Dunn surveyed 153 conservative professors for their 2016 study Passing on the Right: Conservative Professors in the Progressive University. The authors wrote that these professors sometimes have to use "coping strategies that gays and lesbians have used in the military and other inhospitable work environments" in order to preserve their political identity. One tactic used by about one-third of the professors was to "pass" (or pretend) to hold liberal views around their colleagues. Shields stated his view that the populist right may overstate the bias that does exist and that conservatives can succeed using mechanisms like academic tenure to protect their freedom.