More than 60 MPs have signed a letter to the home secretary calling for the easing of COVID-19 restrictions to allow protests to go ahead.

The letter to Priti Patel, organised by campaigns group Liberty and Big Brother Watch, warns that allowing the police to criminalise people for protesting “is not acceptable and is arguably not lawful”.

Under current restrictions, it is unlawful for groups to gather for protests and police have warned people on Saturday not to head to central London for planned demonstrations, including by anti-lockdown campaigners.

The letter follows last week’s outcry over the Metropolitan Police’s handling of the vigil on Clapham Common in memory of Sarah Everard.

It said such “shocking scenes” were “entirely avoidable” if the government had provided guidance to police and ensured protests were clearly exempt from the ban on gatherings under lockdown.

Signatories of the letter include Tory MPs Sir Charles Walker, Steve Baker, Sir Christopher Chope and Sir Desmond Swayne and the Liberal Democrat leader Sir Ed Davey.

Sam Grant, head of policy and campaigns at Liberty, said: “In a healthy democracy, protest is a critical way we can fight for what we believe in.

More from Covid-19

“The government’s current quasi-ban on protest is completely unacceptable.

“Last week, the police conceded protest is not banned under the lockdown regulations, but used them to threaten then arrest demonstrators anyway.

The home secretary must immediately issue guidance to all police forces to ensure socially distanced protests can go ahead and create an explicit exemption for protest in the current regulations.”

Big Brother Watch director Silkie Carlo said: “A country cannot be described as a democracy if people do not have the freedom to protest.

“The harrowing scenes of police officers using force against women at Clapham Common recently were avoidable and wrong.

“Over the past week, many more demonstrators and even legal observers have been arrested or fined.

“This stain on our democracy is a direct consequence of this government’s disrespect for the most basic of British democratic freedoms.”

In response, a government spokesperson said: “While we are still in a pandemic, we continue to urge people to avoid mass gatherings, in line with wider coronavirus restrictions.”