As she won the South Shields by-election, Labour's Emma Lewell-Buck said the coalition Government was taking the country in the wrong direction.
In her maiden speech, she said: "Mr Cameron, when working families need a Government on their side, you made them pay for a tax cut for millionaires."
More top news
A BBC chief said reporters also had a responsibility to be sensitive in their broadcasts.
Ruth Smeeth is due to give evidence at a hearing involving party member Marc Wadsworth.
In the latest in the franchise, Marvel's superheroes assemble en-masse to face their biggest challenge yet.