The space in which charities can speak out on important issues is narrowing because of recent government policies, according to the think tank New Philanthropy Capital.
In a submission to the House of Lords Select Committee on Charities, NPC says policies such as the lobbying act, the proposed so-called "gagging clause" – which would prevent charities that receive public money from lobbying government – and the Charity Commission’s guidance on campaigning during the EU referendum were creating an "ever more hostile environment" for charities that want to speak out.
The submission says these recent reforms "have created an atmosphere in which many charities fear that their voice, and by extension the voice of those they exist to help, is being silenced".
It says "the sector has a legitimate role in raising issues that matter to beneficiaries, and society overall loses out if this role is restricted".
The NPC submission warns that the charity sector has also made a number of errors, including "avoidable fundraising and governance scandals".
NPC says that a "more diverse trustee base", better representation on boards of new skills such as expertise in digital technology and making boards report on their impact and governance processes to the Charity Commission should be considered.
It says charities need greater transparency and accountability to the public to retain public trust.
The submission says the charity sector is "poorly prepared" for the challenges posed by an ageing population and digital technology, and says the financial pressure on charities is "greater than it has been in previous years".
According to the submission, the changing role of the state "has profound implications for some charities", with smaller and more specialist charities often locked out from working with local and national government because of the shift from grants to commissioning and an increased focus on commissioning out larger contracts.
Patrick Murray, head of policy and external affairs at NPC and the author of the submission, said: "Charities feel a bit battered and bruised from the last year or two. For a long time the voluntary sector got along without a whole lot of media and public scrutiny. Now, after some seriously poor practices have been exposed, charities have a big job ahead to win back public trust.
"It is not up to government or the regulator to be cheerleaders for the sector, but they do have a role to play in encouraging transparency and good governance, which underpin public trust in charities. In doing this, it is vital that government does not restrain charities from doing their essential work.
"Charities evidently feel that the rules have tipped too far against them. The challenge now is for ministers to listen to these concerns properly and for charities to make sure that they remain relevant to the changing world."