This week on Moyers & Company (check local listings), more from author and legal scholar Ian Haney Lopez as he talks further with Bill about dog whistle politics - code words that use race to turn Americans against each other. Politicians manipulate deep prejudice to rouse hostility against minorities and the government, and summon support for policies that make economic inequality even worse. According to Haney Lopez, "This use of race has allowed an extreme faction of conservatives, those most dedicated to the power of big money, to the power of corporations to not only hijack American democracy, but to hijack the Republican Party." He reviews the use of the dog whistle in recent political history, from the "Southern strategy" developed by Republicans in the 60s and Democratic President Bill Clinton's welfare reform and anti-crime policies, to the tea party movement - which he says has legitimate issues but has "accepted the conservative line that was happened in their lives is really the fault of minorities" -- and current attacks on President Obama's Affordable Care Act: "The subtext is, 'Here comes a black man who exemplifies the way in which the Federal government is now by and for minorities." "Dog whistling" is going to evolve, Haney Lopez says "in a way that brings in certain portions of the Latino population, certain portions of the Asian population, that's what it's likely to do. Unless we start addressing this within minority communities, but also in terms of national politics, we should expect these sorts of racial provocations to continue to define our politics for the next decade, two decades, three decades." Ian Haney Lopez, a professor of law at the University of California, Berkeley, is a senior fellow at the policy analysis and advocacy group, Demos.