Viewers could easily have confused it for a Labour Party political broadcast. Indeed, what I found myself watching on television on Sunday night seemed to fit the bill perfectly.

At first sight, it was the glossiest, starriest and most expensive party commercial in British campaigning history.

The storyline was written by Harry Potter author J.K. Rowling; the all-star cast included Sir Michael Gambon and Keeley Hawes; the budget was in excess of £5 million.

The Casual Vacancy: At first sight, it was the glossiest, starriest and most expensive party commercial in British campaigning history. But, in fact, it wasn’t produced by the Labour Party

But, in fact, it wasn’t produced by the Labour Party.

It was BBC TV’s adaptation of Labour-supporting Rowling’s first novel for adults, The Casual Vacancy — a tub-thumpingly political drama featuring well-heeled Conservative-voting types behaving selfishly and badly in an idyllic Cotswold town very similar to Witney, whose MP is . . . David Cameron.

To those of us of a cynical disposition, it seemed as if someone at the BBC had deliberately decided to screen this farrago of Left-wing propaganda just three months before the General Election in order to mock the Tories.

Indeed, I am clearly not alone in feeling a sense of deep disquiet about the behaviour of the state broadcasting corporation, to which people of all political opinions have to subsidise via the compulsory licence fee.

The Tory MP and former Foreign Secretary Sir Malcolm Rifkind complained of The Casual Vacancy: ‘In the run-up to a General Election, the Government quite rightly has to go into purdah and refrain from doing anything provocative. I think the BBC should have to apply the same criteria.’

But it’s not just the Tories who have cause to be peeved by the recent output of our (supposedly) neutral, public service broadcast channels.

So, too, does Ukip leader Nigel Farage, who last night was the victim of a hatchet-job so blatant it might just as well have been called: ‘Vote Farage, Get Hitler!’

In the Channel 4 ‘mockumentary’ Ukip: The First 100 Days, viewers were invited to imagine how Britain might look three months after a shock General Election victory by Nigel Farage and the setting up of a Ukip government.

Channel 4 'mockumentary': Ukip leader Nigel Farage was last night the victim of a hatchet-job so blatant it might just as well have been called: 'Vote Farage, Get Hitler!'

Now, you hardly need to be a card-carrying Ukip member to be able to concede that there might be at least some entertainment value in such an extraordinarily unlikely event: the bravura spats with European Commission President Jean-Claude Juncker; the Mister Toad antics of Farage in his mustard coloured corduroys at Number 10; the dismantling of every wind turbine in Britain . . .

This being Channel 4, however, the programme’s makers saw cause only to spread fear and alarm among voters — not merriment.

Unhappy; Tory MP and former Foreign Secretary Sir Malcolm Rifkind was peeved by The Casual Vacancy

In order to give viewers the ‘correct’ Left-wing perspective, the drama invited us to witness Ukip’s rise mainly through the eyes of a fictional female Ukip MP, a Sikh called Deepa Kaur.

Needless to say, she was soon made to see the error of her ways, exploited by the party’s cynical hierarchy as its token Asian, continually upset by ‘typical’ Ukip voters who made comments about immigrants such as ‘Send them all back!’, hastily qualified by, ‘No, not you, luv, obviously, you’re different . . .’

Yes, of course it was only fiction, but it was fiction carefully staged in such a way as to render it almost indistinguishable from real life.

Veteran election-night broadcaster Peter Snow played himself as he convincingly announced the election results with the latest fancy computer graphics, with news clips of the real former Tory-MP-turned-Ukip activist Neil Hamilton (captioned: ‘Deputy Prime Minister’) calling for a clampdown on immigrants.

There was also Labour MP Diane Abbott and Lib Dem leader Nick Clegg telling us (in case we hadn’t got the message) how racist Ukip is; footage of Farage on a car journey to Downing Street; and a reporter tracking Deepa Kaur for a series of fly-on-the-wall-style interviews as we followed her path from elation to disillusionment and despair.

Channel 4 — which is publicly owned and has a ‘public service remit’ — has defended the programme by saying: ‘Our job is to reflect and explore contemporary British life. Nothing represents what’s different and unique in British political life now more than the rise of Ukip.’

All this may be true, but it completely ducks the issue of the drama’s shameless political bias. This was Ukip presented very much from the Left’s perspective: as racist, chauvinistic and jingoistic.

Even the programme’s economic analysis might have been scripted by Labour Shadow Chancellor Ed Balls, such as the scene where we were shown that Britain’s exit from the EU is apparently going to lead to a massive wave of redundancies.

'Ukip: The First 100 Days': Of course it was only fiction, but it was fiction carefully staged in such a way as to render it almost indistinguishable from real life

Had Channel 4 really wanted to have fun with a dystopian vision of an unlikely election result, it would surely have been better off imagining the Green Party in Number 10: with policies including the end of economic growth, the dismantling of the Armed Forces, and unlimited immigration.

There’s a party that really would bring about misery and chaos.

But, of course, the Greens would never get the same kind of unfavourable scrutiny because their politics align so much more closely than Ukip’s do with the metropolitan, liberal types who dominate our state-controlled broadcasters.

The BBC said Robert Peston's The Price Of Inequality series on Radio 4 'explored the alarmingly widening gap between rich and poor since the 1980s'

This is the true scandal of The Casual Vacancy and Ukip: The First 100 Days.

It’s not that they have technically broken any rules on political broadcasting in the run-up to a General Election, but rather that they so blatantly flout the spirit of the statutory regulations obliging our public broadcasters to be fair, balanced and politically neutral.

Of course, BBC and Channel 4 executives regularly claim that because they receive complaints from all political parties, they are clearly getting the balance about right. In truth, though, the bias is almost always in one direction.

Consider, for example, the timing of BBC Panorama’s recent revelations about the bank HSBC, calculated to make the Tories look like a party of spivs and chancers who care only about the rich.

Or Robert Peston’s The Price Of Inequality series on Radio 4 — which the BBC said ‘explored the alarmingly widening gap between rich and poor since the 1980s’.

Or C4’s documentary How Rich Are You?, which looked at wealth in a Britain ‘polarised between bling and benefits’.

Or the BBC’s The Super-Rich And Us, about international billionaires who live in Britain, buy football clubs, and pay minimal tax, while the poor get poorer.

Each of these programmes fits so perfectly with Labour’s current campaign narrative, that ‘the rich are getting richer and the poor poorer’ that you might almost think they’d been personally scripted by Labour’s spin doctors.

Perhaps I’m wrong, but I don’t recall any recent BBC or Channel 4 programmes — fictional or non-fictional — arguing for smaller government or against political correctness or telling us how the economy is finally beginning to recover after a decade of Labour mismanagement.

The Casual Vacancy is a tub-thumpingly political drama featuring well-heeled Conservative-voting types behaving selfishly and badly in an idyllic Cotswold town very similar to Witney, whose MP is... David Cameron

Only last week, I made this point in an interview with the BBC as part of a series commissioned for a forthcoming Royal Television Society lecture on the future of public service broadcasting.

I said that, like communism, public service broadcasting is a great idea in principle but a terrible idea in practice because, however noble the intentions, what we end up with is a self-appointed elite imposing their warped, biased values on the rest of us, whether we like it or not.

So entrenched is that bias that I expect half the time our broadcasters are not even aware of it

So entrenched is that bias that I expect half the time our broadcasters are not even aware of it.

That would explain the toe-curling scene in The Casual Vacancy where local solicitor and champion of the underdog Barry Fairbrother (played by Rory Kinnear) delivered a long-winded speech in which he suggested that turning the village’s local food bank-cum-drug treatment centre into a spa hotel was the sort of thing we fought Nazi Germany to prevent.

Any half-sensible script editor would have drawn a red pencil through such lines straight-away. (Not that any sensible editor would have commissioned it in the first place).

But in BBC-land and Channel 4-world, this kind of sixth-form socialism is seen as the way all decent people think.