On 31 October The Canary launched another of its many attacks on BBC political editor Laura Kuenssberg.
Kuenssberg, paid over £220,000 a year and with a posh background, is not left-wing. The Canary is self-professedly "progressive".
But The Canary's attack serves not to reveal facts ignored or tucked away by the BBC and similar media; rather, to try to stifle necessary critical debate within the labour movement by claiming that there is no issue other than mischief-making by the media.
Kuenssberg was tweeting from "Prime Minister's Questions" in Parliament about the Budget.
"Corbyn", she wrote, "has plenty of ammo on ‘broken promise budget’ - but then walks into a trap on income tax cuts that Labour leadership won’t unpick".
"PM predictably slams back with McDonnell's backing of the cuts for higher rate payers... Corbyn doesn’t answer it but moves on to cuts to benefits that are still going ahead".
The Canary's take on all this: Kuenssberg doesn't understand the concept of Prime Minister's Questions. It was for May to answer questions, not Corbyn.
It's not unusual to retaliate to a difficult question by firing another question back at the questioner.
Corbyn might have reasonably said: "we'll deal with that another time", in order not to get steered off-track. But there's nothing out-of-order about Kuenssberg reporting that.
And in fact it wasn't a matter just of Corbyn refusing to be diverted. There is a real issue.
The Tories' income tax cuts benefit everyone paying tax, but those earning over £50k more than most of us.
John McDonnell responded that he would not reverse the Tories' cuts, but he would stick to Labour's previous policy of adding a new rate for those earning over £85k. Thus he committed to keep the Tories' tax cuts for everyone earning less than £85k.
By the most recent figures from the Office of National Statistics, a £50k income is about the 89th percentile while £85k is more than the 96th percentile. So this means Labour keeping Tory tax cuts for even most of the top 10% of earners.
McDonnell said: "Some of these are middle earners, headteachers and people like that, who've had a rough time of it, as well as everyone else".
Head teachers, except perhaps those in small primary schools, are not "middle earners", other than by the standards of MPs and top newspaper journalists. They are well-paid bosses, and usually bullying and destructive bosses at that.
The right-wing and "centrist" Labour MPs who refused to vote for the Tory tax cuts were surely hypocritical, and just seizing on a chance to appear "left-wing" which (because of their politics) comes rarely to them.
But it is a reasonable question to ask: is it possible for a left-wing policy, even limited to reversing the cuts and restoring standards to something like 2010, to get through without squeezing a bit more from the top 10%?
Debate on such issues should not be shut down.