Some gamblers recently made big profits by placing bets on the ouster of Iran's supreme leader Ali Khamenei on prediction markets such as Polymarket and Kalshi. Alex Goldenberg, a fellow at Rutgers University's Miller Center, breaks down how these online platforms work and why they're facing backlash for allowing wagers on geopolitical events, including fears of insider trading. »»» Subscribe to CBC News to watch more videos: http://bit.ly/1RreYWS For breaking news, video, audio and in-depth