MSNBC's Ari Melber hosts "The Beat" on Friday, May 23, and reports on President Trump's "retribution campaign." Melber is also joined by Erin Brockovich, consumer advocate and environmental activist, to discuss the Trump administration's push for deregulation. Plus, three-time Grammy winner Diplo appears in the latest installment of "Mavericks." Eugene Robinson and Chai Komanduri also join.
