George Monbiot is surely right that large private donations poison democratic trust, whether or not corruption can ever be shown ( Political donations are poison to our democracy – but there’s an easy antidote to that, 30 April ). The damage lies not only in any favour bought but in the suspicion created. When one billionaire can appear to sustain a political party, politics begins to look less like representation and more like private ownership. Monbiot’s membership-based model has moral weight. It would force parties to organise among citizens rather than flatter wealth and it would make politicians seek members, not patrons. That alone would change the culture. But I am not convinced that membership should be the sole measure of democratic legitimacy. Membership favours parties with highly motivated activist bases. At one moment that might benefit the Greens; in another it might benefit Reform UK, the Scottish National party, or any party able to mobilise a surge.…