What makes an expert?

What makes someone an expert, and how do BBC producers decide who has the right expertise to appear on air? In this episode of Over To You, we hear listeners’ views on who they trust and why. We go behind the scenes with The Engineers and CrowdScience to find out how programmes choose their contributors, and explore the editorial principles behind using experts on the BBC. Plus, as more of us encounter experts through TikTok, Instagram and YouTube, we ask how social media is changing who we see as an authority. We also speak to BBC Verify about how it assesses expertise and decides who and what audiences can trust.