My vote was a plea for Labour to tackle child poverty. Its response? To suspend me | John McDonnell

What is it that drove, on Tuesday night, seven Labour MPs to vote for an amendment tabled in parliament by another party, with the virtual certainty of losing the party whip as a consequence? The answer is that some issues are so important, so pressing and so at the core of one’s beliefs that the seriousness of the risk demonstrates the seriousness of the issue at stake.

The revulsion at witnessing large-scale child poverty in our society was one of the key motivating factors for the early socialists who came together to found the Labour party. Establishing a system to end poverty and provide security to all families was at the heart of the postwar Attlee government’s welfare state.

After child poverty soared under the Thatcher administration , Gordon Brown railed against it and dedicated the incoming New Labour government to eradicating child poverty once and for all. In office, he worked hard to be true to his word and his policies lifted about a million children out of relative poverty.

All that progress was halted and reversed by the brutality of the austerity programme of the David Cameron and George Osborne government, which paid for its tax cuts to corporations and the wealthy by targeting children, among others, for cuts in benefits and services.

The result is that after 14 years of Conservative governments, more than 4 million children now live in relative poverty. In 2022, more than a million of them experienced destitution : lacking the essentials to be adequately fed, kept warm and clothed.

The two-child cap on benefits was one of the cruellest policies of the Osborne era. It means no benefits are paid for the third or any subsequent children in a family. It affects more than 1.5 million children. Just the simple measure of scrapping this cap would lift about 300,000 children out of poverty.

That’s what the king’s speech amendment was all about. It wasn’t about rejecting or voting against the king’s speech programme. It was a plea to include this basic reform in the programme.

Prior to the election, many Labour MPs and supporters, like me, were really pleased to see a commitment to introducing an anti-poverty strategy. Our argument was that scrapping the cap could be the first significant step in the strategy.

Although Labour had set out its first-steps policy programme and had not included this measure, the budget preparation was under way quickly after the election; it is becoming increasingly apparent that the chancellor has left herself sufficient flexibility on estimates of growth and additional taxation measures to accommodate the measure. The cost is estimated at an initial £1.7bn, eventually rising to £3.4bn.

A campaign to scrap the cap attracted the support of more than 120 civil society organisations, including the main national poverty campaigns, religious bodies and trade unions. The pressure from this campaign and Labour MPs resulted in ministers announcing last week the setting up of a taskforce on child poverty.

However, the king’s speech contained no commitment to scrapping the cap, no timescale for the taskforce’s work to be completed, and no deadline for decision-making on issues such as the cap.

The concern grew that the reason for not committing to scrapping the cap was neither funding nor the timescale for practical implementation by the taskforce. Instead, the fear is that, behind the scenes, party strategists were looking at polls and focus groups, and seeing that the cap was popular among some potential supporters. Not wanting to alienate them would mean ignoring a few hundred thousand children in poverty.

Seven Labour MPs, myself included, voting for an amendment when the government has such an overwhelming majority will be criticised by some as futile or gesture politics.

Of course, I disagree.

First, the stance taken has brought so much more welcome attention to the issue of child poverty and the impact of the egregious two-child cap. It is motivating campaigners to focus action in the forthcoming budget on child poverty.

Second, it has meant that the government will inevitably have to address this issue, and has increased significantly the likelihood that the government will abolish the cap.

Third, it has demonstrated that MPs, if they believe something is right, are willing to risk everything and stand by their cause.

At a time when trust in our political system is at an all-time low, maybe from time to time some small interventions of this kind are needed to lift our spirits and confidence in our democracy.

• John McDonnell has been the MP for Hayes and Harlington since 1997. He was shadow chancellor from 2015 to 2020