David Tennant is the latest “Harry Potter” actor to be called out by J.K. Rowling for publicly supporting trans rights. It all started when Tennant, the “Doctor Who” favorite who also played Barty Crouch Jr. in “Harry Potter and the Goblet of Fire,” accepted a prize at the British LGBT Awards and called out Kemi Badenoch, the U.K. Minister for Women and Equalities who has said she would exclude trans women from certain spaces.

In his acceptance speech, Tennant said that he was “a little depressed” over getting an award for simply saying obvious facts like “everyone has the right to be who they want to be and live their life how they want to live it as long as they’re not hurting anyone.”

“It’s human decency,” Tennant added. “We shouldn’t live in a world where that is worth remarking on. However until we wake up...