Conservatives battle over resignation of Heritage Foundation scholar The resignation of the Heritage Foundation scholar who helped write an economic-impact study on the Senate immigration bill has triggered a impassioned skirmish among conservatives -- who are divided over whether Jason Richwine was unfairly targeted for a racially charged dissertation from his past. The back-and-forth appeared to start in earnest Friday morning, hours before Richwine would resign from the conservative think tank. After the publication of a Heritage study which claimed the immigration bill would cost taxpayers more than $6 trillion, attention was drawn to Richwine's Harvard doctoral dissertation which said that the average IQ of Hispanics and other immigrants is lower than that of the country's white "native" population and that the disparity will likely persist over generations. Conservative pundit Michelle Malkin appeared to be among the first to weigh in when she argued that supporters of the immigration bill - apparently upset with the Heritage report arguing the legislation would burden the economy with more low-skilled workers -- unfairly branded Richwine and the entire Heritage operation "racist." She pointed the finger at pundits on both sides of the aisle. "The smug dismissal of Richwine's credentials and scholarship is to be expected by liberal hacks and clown operatives," Malkin wrote in her "Human Events" magazine column titled "The Crucifixion of Jason Richwine." But a reckless and cowardly pileup of knee-jerk dilettantes on the right has joined the character assassins of the Soros-sphere, MSNBC and Mother Jones in deeming Richwine a racist. Among those on the right whom Malkin criticized was Jennifer Rubin, a conservative Washington Post blogger. Rubin in a column Friday appeared to put much of the blame for the Richwine flap on Heritage's new leader Jim DeMint, the former South Carolina Republican senator. "Although the study was developed under former President Edwin "Ed" Feulner's watch, some Heritage scholars expressed their concern about the scholarship," Rubin wrote. No one from Heritage with whom I spoke was aware that Richwine had written a thesis and had spoken openly on his contention that Hispanics have lower IQs, in part because of genetics. In part, the incident reflects on DeMint and a cadre of hard-hitting GOP activists and former Hill staffers he brought with him. Erick Erickson, of the conservative blog site Red State, in turn piled on Rubin, accusing her of trying to "throw Jim DeMint under a bus" and suggesting her arguments are "stupid." "Rubin has a history of bashing DeMint for being a conservative while she, ironically, poses as a conservative voice at The Washington Post," Erickson added. The Heritage Foundation released a statement Friday that said Richwine had resigned without offering many details. "Jason Richwine let us know he's decided to resign from his position," the statement read. He's no longer employed by Heritage. It is our long-standing policy not to discuss internal personnel matters. However, the infighting appears far from over. Charles Murray, a scholar for the American Enterprise Institute, another Washington-based conservative think tank, suggested Heritage didn't stand behind Richwine. Thank God I was working for Chris DeMuth and AEI, not Jim DeMint and Heritage, when The Bell Curve was published. Integrity. Loyalty. Balls," he tweeted. Murphy co-authored the 1994 book "The Bell Curve: Intelligence and Class Structure in American Life" that included research and discussion on the racial differences in intelligence.