Cuts that affect voluntary sector organisations are being made amid a "growing scrutiny deficit" of weakening local accountability, according to Sir Stephen Bubb.
The head of Acevo will use tonight's speech at a London event marking the 25th anniversary of the chief executives body to warn that cuts to voluntary sector resources will worsen in relative terms over the coming years.
"These cuts are being implemented in the midst of a growing scrutiny deficit," he will say. "Power is being devolved to an increasingly local level; but that power is not being accompanied by greater accountability."
He will say that interest in democracy at a local level is low and the power of local media weak "and in many cases dying or non-existent".
"The central apparatus that once would have interrogated local decision-making, in the form of organisations like the Audit Commission, is being pared back or abolished," Bubb will say. "And while charities might seek to act as the ‘armchair auditors’ that the government has spoken of, too often what they come up against is poor-quality information or none."
Bubb will also warn that the cuts affecting voluntary sector organisations have barely begun to bite: ""They are clearly set to last not just for the period they have been planned for, but well beyond the current parliament too."
He will say that third sector leaders are concerned that public attitudes to charities that rely on public funding are hardening, "with greater suspicion of those who rely on publicly funded support".
He will warn that we risk creating a "forgotten Britain" in which groups such as homeless people, older people and people with mental health problems face a worsening plight invisible to most of society.
In response, he will say, government must "rediscover its urgency on genuine public service reform".
"There is a brutal logic at play: if you remove billions from public services and do not reform them, the people who rely on them suffer. As one Acevo member said to me: ‘Spending less is not necessarily a disaster, but spending less and trying to do things the same way is.’
"So let us hope that as the government seeks to re-establish its sense of purpose over the coming year, public service reforms are central to it – reforms like implementing the Dilnot report on social care funding, making better use of the third sector in tackling reoffending or taking a more preventative approach in health."