Carl Sargeant (pictured), 49, had told friends that, since the nature of the charges had not been disclosed to him, he felt unable to offer any defence

Until the Fifties, the lynch mob was one of the ugliest aspects of American life.

In segregated Southern states, whites seized victims — almost invariably black men accused of raping or merely behaving disrespectfully towards white women — and hanged them.

The supposed offenders, who early in the last century were numbered in hundreds, were often later found to be innocent. But by then they were dead, and, anyway, only a few liberal do-gooders cared.

Today, in Britain, we are in danger of reviving that repugnant culture.

Almost daily we see terrible charges laid against both the living and the dead, broadcast through social media, inflicting grievous pain on a host of people, some of whom have done nothing wrong at all, while others have done nothing so base as to deserve public branding.

It happens in flagrant defiance of libel and slander law, without obligation to produce a shred of proof.

This week, a senior Labour politician killed himself, having been suspended by the Welsh government following unspecified allegations of sexual harassment.

Carl Sargeant, 49, had told friends that, since the nature of the charges had not been disclosed to him, he felt unable to offer any defence.

I know nothing of the misdeeds Sargeant may, or may not, have committed. But it seems profoundly shocking that he should have been driven to take his own life, without the allegations being revealed. His family say they concerned ‘unwanted attention, touching and groping’.

It is only the most dramatic of a long succession of brutal claims: people — including children — are daily sentenced to public embarrassment or outright disgrace, without examination of evidence, or a jury’s verdict.

In 2012, Lord McAlpine, a former Tory treasurer, was falsely alleged by BBC2’s Newsnight — though at first not named — to be a child abuser. The Commons Speaker’s wife, Sally Bercow, had to pay £15,000 damages for joining the odious persecution of McAlpine which went viral on social media.

Hounding

McAlpine gave the money to the Chelsea Pensioners, shortly before his 2014 death, which friends said had been hastened by this wicked libel.

Meanwhile, BBC presenter Mark Lawson, a fine broadcaster, was summarily dismissed in 2014 from a long-serving role on Radio 4’s Front Row arts programme for alleged ‘bullying’ of colleagues, after which he suffered a nervous breakdown.

People who should have known better, some seemingly motivated by personal grudges, joined a witch-hunt against him on Twitter and Facebook.

In 2012, Lord McAlpine (pictured), a former Tory treasurer, was falsely alleged by BBC2’s Newsnight — though at first not named — to be a child abuser. The Commons Speaker’s wife, Sally Bercow, had to pay £15,000 damages for joining the odious persecution of McAlpine which went viral on social media

I have written about the appalling treatment of Field-Marshal Lord Bramall and the late Edward Heath. It seems extraordinary that former Metropolitan Police Commissioner Bernard Hogan-Howe should recently have been granted a peerage, given his role in hounding Bramall — an investigation worthy of East Germany’s Stasi.

It is even more appalling that Wiltshire’s chief constable, Mike Veale, is said to be planning a handsomely pensioned retirement, after smearing the long-deceased Edward Heath.

Mr Veale brought public disgust upon himself by announcing that, had Heath still been alive, he would have been interviewed under caution, despite his force’s inquiry having failed to find a wisp of plausible evidence of wrongdoing.

What is happening to us, as a society? How can people — never mind the police — treat fellow citizens, living or dead, with such cruelty? Do we no longer care for the great principle of ‘innocent until proven guilty’?

It is even more appalling that Wiltshire’s chief constable, Mike Veale, is said to be planning a handsomely pensioned retirement, after smearing the long-deceased Edward Heath (pictured)

Social media bears a huge responsibility — it makes possible the propagation of outrageous charges, without accusers being identified or needing to justify themselves, far less of the laws of slander or libel being invoked.

Some years ago, I received a letter from a man with whom I was at Charterhouse School, then serving a prison sentence for sexual offences. ‘How would you feel,’ he asked, ‘if I now falsely accused you of having assaulted me behind the bike sheds at Charterhouse?’

I responded with a flippancy I would not dare employ today, saying it was implausible, because at 15 I was irredeemably unattractive to both sexes.

Now, I find it frighteningly possible that, when public passions run so high and online malevolence is so easy to vent, someone could lay sexual allegations against me at the touch of a button. I am no more nor less guilty than Edwin Bramall.

Since my former schoolfellow was convicted in a court, I had little doubt that (though I regretted it, because I liked him) he was guilty as charged.

But Welsh Assembly member Carl Sargeant was never charged with anything; nor was the BBC’s Mark Lawson, nor the late Edward Heath.

In among the undoubtedly valid allegations of sexual harassment being made against some politicians, we may be certain there are also monstrous fabrications. On another front, the Russians — supreme online saboteurs of justice and democracy — are playing the fake news game in the Baltic states, which they aim to destabilise.

I have written about the appalling treatment of Field-Marshal Lord Bramall (left) and the late Edward Heath. It seems extraordinary that former Metropolitan Police Commissioner Bernard Hogan-Howe should recently have been granted a peerage, given his role in hounding Bramall

Putin’s trolls have spread rumours that the named commanding officer of one Western troop contingent is having an adulterous affair with a Latvian; of another colonel, that he is betraying his wife with a Lithuanian.

This may sound comic: but think of the effect on the morale of soldiers in the region if the Russians succeed in their sophisticated efforts to wreck these officers’ marriages.

Social media already undermines democratic debate on both sides of the Atlantic with a diet of fake news which far too many people swallow.

Salacious

Now, unsourced allegations threaten also to overwhelm decent values. I am dismayed by the number of supposedly educated people I meet, still determined to believe Edward Heath guilty of sexual offences, tittering ‘no smoke without fire’. But there often is.

As a newspaper editor for 16 years, I can testify that a great many delicious, salacious rumours about public figures are absolutely unfounded.

Anger increases rather than diminishes with time towards Sir Brian Leveson (pictured), the foolish judge who produced a 2012 report condemning Press excesses while making no recommendations to regulate social media or non-newspaper websites

Most people, whether famous or obscure, live rather more respectable lives than gossip-mongers would like us to believe. Our Parliament, like other legislatures around the world, is sooner or later going to have to grasp the infinitely prickly nettle of taming social media, imposing regulation which must include a requirement to disclose the identities of libellers and slanderers.

Anger increases rather than diminishes with time towards Sir Brian Leveson, the foolish judge who produced a 2012 report condemning Press excesses while making no recommendations to regulate social media or non-newspaper websites.

He concluded that: ‘People will not assume that what they read on the internet is trustworthy.’

Deplorable

Some of us said then that, however deplorable some newspapers’ behaviour — phone-hacking and suchlike — it was absurd to deploy a sledgehammer against print media while blithely ignoring the vastly more frightening threat posed by Twitter, Facebook and their kin.

The RAND corporation, one of the U.S.’s foremost think-tanks, recently spoke of Russia using social media to deliver ‘a firehose of falsehood’, and it was not wrong.

Let me end where I started.

Welsh Cabinet minister Carl Sargeant may be shown to have behaved badly towards women. It should nonetheless be a source of shame to the rest of us, British society, that he was driven to kill himself without any specific charge, let alone a criminal indictment, being laid.

His family say he was ‘denied natural justice’, and they are right. The influence of social media upon us all is certainly malign, arguably evil.

Unless we recognise the new lynch mob for what it is — and find a way to cage it — this electronic wild beast will devour values that are indispensable to any civilised society, fairness and trust foremost among them.