I think b/c politicians are expected to lie.
Whereas scientists are viewed as naiive cute furry animals that wouldn't spin the truth.
You never hear them take a scientist to task or ask probing questions.
It's really a different type of interview - where the holy gurus of academia are blessing the reporter with knowledge
I enjoy their Behind the Stats podcast:
https://www.bbc.com/audio/series/p02nrss1
(though also often sloppy)
I think b/c politicians are expected to lie. Whereas scientists are viewed as naiive cute furry animals that wouldn't spin the truth. You never hear them take a scientist to task or ask probing questions. It's really a different type of interview - where the holy gurus of academia are blessing the reporter with knowledge