After shocking video footage was released of the 29-year-old African-American being beaten to death by five black police officers in Memphis, we ask what might stop police brutality in the US. Sarah and her BBC colleague Chelsea Bailey share insights from their reporting trips to Memphis. And we also ask retired African-American LAPD Sergeant Cheryl Dorsey what should be done differently. With Donald Trump revving up his presidential campaign in South Carolina, the Americast team discusses the two other Republicans who are set to challenge him: Ron DeSantis and Nikki Haley. Americast is presented by North America editor Sarah Smith, Today host Justin Webb, the BBC's social media and disinformation correspondent Marianna Spring, and North America correspondent Anthony Zurcher. Email [email protected] with your questions and comments and send us a message or voice note via WhatsApp, to 03301239480. Find out more about our "undercover voters" here: https://www.bbc.co.uk/news/world-us-canada-63530374. This episode was made by Phil Marzouk and Rufus Gray. The studio director was Mike Regaard. The assistant editor was Simon Watts. The senior news editor was Sam Bonham.