More than 40 MPs and peers have joined calls from 13 human rights groups, lawyers and campaigners for the National Police Chiefs' Council (NPCC) to look again at penalties handed out to those apparently flouting the rules.
A total of 18,439 fixed penalty notices (FPNs) including 15,856 in England and 2,583 in Wales were recorded by forces between March 27 and June 22, according to provisional NPCC data.
As the country reaches 100 days of lockdown, a letter sent to NPCC chairman Martin Hewitt by the group led by organisation Big Brother Watch said the case for a review was now "extremely compelling".
The letter, seen by the PA news agency, said: "Currently, the NPCC has neither acknowledged the systemic issue of unlawful, inconsistent and discriminatory enforcement of emergency laws, nor taken the initiative to support reviews by police forces of FPNs (fixed penalty notices).
"No reasons were given as to why the NPCC does not support a review.
"The only means to ensure injustices are recognised and remedied is to review all fines already issued."
Former Conservative cabinet minister Andrew Mitchell, ex-Labour leader Jeremy Corbyn and acting Liberal Democrat leader Ed Davey as well as Baroness Shami Chakrabarti are among those to put their name to the letter alongside groups including Amnesty International UK and Liberty.
Reverend Martin Poole, the Brighton vicar who asked Health Secretary Matt Hancock to review all lockdown fines during one of the Government's daily press briefings in May in the wake of the Dominic Cummings affair, also backed the calls.
Describing the laws as "draconian" and "the most severe restrictions of rights and freedoms" since the Second World War, the letter claimed statistics published so far indicate there is a "postcode lottery" of where fines are being issued.
It raised concerns of suggestions disproportionate numbers of fines were being handed to black and Asian people - describing this as "evidence of racism, discrimination and bias".
North Yorkshire Police has issued the most fines so far (1,122), followed by the Metropolitan Police (1,072) and Devon and Cornwall (978) compared to just 42 in Staffordshire and 58 in Warwickshire.
Analysis by the PA news agency of NPCC data on fines issued in England and Wales between March 27 and June 22 suggested the rate was 47% higher for those given to people who were not white.
Comparing the number of fines to the population, using estimates broken down by ethnicity from the Office for National Statistics, indicated the number handed to white people was around 23 per every 100,000.
For those from BAME backgrounds, this was 34 fines per 100,000 people.
It emerged earlier this month that wrongful prosecutions were still taking place under the emergency legislation brought in to enforce the measures put in place in a bid to curb the spread of the virus.
The Crown Prosecution Service is continuing to review all such prosecutions following a string of errors highlighted by journalists, lawyers and campaigners.
Big Brother Watch director Silkie Carlo said there had been "no justice for the thousands of people we estimate have been wrongly penalised with fines".
In an earlier response, Mr Hewitt welcomed "proper scrutiny" of the use of the powers but said it was "not for the NPCC to review the work of individual forces."
He insisted enforcement was always a "last resort", adding: "Where mistakes have been made, we have recognised this."
Last week the NPCC faced criticism for the time it was taking to publish detailed data on the ethnicity of people being fined.
A spokesman for the body said: "The letter has been received and is being properly considered. There will be a publication of our ethnicity analysis in July."