With results due this week in a sinking ad market, the show was a timely reminder of what broadcast TV can do

When Alan Bates took his campaign for justice to Westminster again last week, it would not just have been the hundreds of post office operators he represents who would have been pleased by his persistence. Carolyn McCall, chief executive of ITV, will doubtless be delighted at the wide-ranging political impact of the broadcaster’s hit drama Mr Bates vs the Post Office, which ignited public anger over the slow-burning Horizon scandal.

As she prepares to present annual results this week, the jury is still out on McCall’s strategy as she attempts to counter the inevitable long-term decline in traditional TV viewership with growth in digital audiences. The Bates drama pulled in 4 million viewers an episode when it was shown, and a further 10 million through the channel’s on-demand service, ITVX.