In recent years, Putnam has been engaged in a comprehensive study of the relationship between
trust within communities and their ethnic diversity. His conclusion based on over 40 cases and 30,000 people within the United States is that in the short term, other things being equal,
more diversity in a community is associated with
less trust both among and within ethnic groups. Putnam describes people of all races, sex, socioeconomic statuses, and ages as "hunkering down", avoiding engagement with their local community as diversity increases. Putnam found that even when controlling for income inequality and crime rates, two factors which
conflict theory states should be prime causal factors in declining inter-ethnic group trust, more diversity is still associated with less communal trust. Further, he found that low communal trust is associated with the same consequences as low social capital. Putnam says, however, that "in the long run immigration and diversity are likely to have important cultural, economic, fiscal, and developmental benefits." and subsequently published the full paper in 2007. Putnam has been criticized for the lag between his initial study and his publication of his article. In 2006, Putnam was quoted in the
Financial Times as saying he had delayed publishing the article until he could "develop proposals to compensate for the negative effects of diversity" (quote from John Lloyd of Financial Times). In 2007, writing in
City Journal,
John Leo questioned whether this suppression of publication was ethical behavior for a scholar, noting that "Academics aren't supposed to withhold negative data until they can suggest antidotes to their findings." On the other hand, Putnam did release the data in 2001 and publicized this fact. Putnam denied allegations he was arguing against diversity in society and contended that his paper had been "twisted" to make a case against race-based admissions to universities. He asserted that his "extensive research and experience confirm the substantial benefits of diversity, including racial and ethnic diversity, to our society." ==Recognition==