In the Derek Chauvin trial, a forensics expert testified on behalf of the defense to cast doubt over what killed George Floyd. Dr. David Fowler says carbon monoxide poisoning is one of several factors that contributed to Floyd's death. Jamie Yuccas is following the trial in Minneapolis. Each weekday morning, "CBS This Morning" co-hosts Gayle King, Anthony Mason and Tony Dokoupil deliver two hours of original reporting, breaking news and top-level newsmaker interviews in an engaging and informative format that challenges the norm in network morning news programs. Subscribe to “CBS This Morning” on YouTube: https://www.youtube.com/user/CBSThisMorning Watch CBSN live: http://cbsn.ws/1PlLpZ7c​ Download the CBS News app: http://cbsn.ws/1Xb1WC8​ Follow "CBS This Morning" on Instagram: http://bit.ly/1Q7NGnY Like "CBS This Morning" on Facebook: http://on.fb.me/1LhtdvI Follow "CBS This Morning" on Twitter: http://bit.ly/1Xj5W3p Subscribe to our newsletter: http://cbsn.ws/1RqHw7T​ Try Paramount+ free: https://bit.ly/2OiW1kZ For video licensing inquiries, contact: [email protected]