The EU referendum debate was dogged by "glaring democratic deficiencies" that left voters feeling "ill-informed" and disengaged, a major report has found.
The Electoral Reform Society (ERS) said its findings show there is a need for a "root and branch review" of how future referendums are carried out.
It found voters felt both the Leave and Remain campaigns turned increasingly negative as the race wore on and many high-profile political figures, including then prime minister David Cameron, were a turn-off.
The society's landmark report, titled It's Good to Talk: Doing referendums differently after the EU vote, comes after the new Prime Minister Theresa May again pledged that "Brexit means Brexit" as the Cabinet begin devising plans for leaving the EU.
Katie Ghose, chief executive of the ERS, said: "This report shows without a shadow of a doubt just how dire the EU referendum debate really was.
"There were glaring democratic deficiencies in the run-up to the vote, with the public feeling totally ill-informed.
"Both sides were viewed as highly negative by voters, while the top-down, personality-based nature of the debate failed to address major policies and issues, leaving the public in the dark.
"It offered a stark contrast to the vibrant, well-informed, grass roots conversation of the Scottish independence vote - a referendum that left a lasting legacy of ongoing public participation in politics and public life."
She said the campaign was too short to foster a proper, engaging debate, and misleading claims were peddled "with total impunity".
She added: "It's time for a root and branch review of referendums, learning the lessons of the EU campaign to make sure the mistakes that were made in terms of regulation, tone and conduct are never repeated."
The report confirms many of the criticisms made at the time of the referendum campaign – that it was too negative and voters were left feeling they did not know the facts.
It found that, despite high levels of interest throughout the campaign, "people felt consistently ill-informed" and "many people simply did not trust the veracity of certain claims made by both sides".
Polling by the ERS showed the intervention of high-profile political figures in the campaign "largely failed to engage or convince voters to their side, with many voters appearing switched off by the "usual suspects".
It appears Mr Cameron's prominent role in the Remain campaign may have backfired, as 29% of voters said he made them more likely to vote Leave whereas just half this number (14%) said he made them want to vote to stay.
The only high-profile figures who, according to the poll, persuaded voters of their position were Boris Johnson, Nigel Farage and Donald Trump, who are all anti-establishment pro-Brexit figures.
Some 29% of those surveyed said Mr Johnson had made them more likely to vote Leave compared with 14% who said he made them want to vote Remain.
Mr Farage persuaded 25% of voters to Leave, although 20% said he made them want to stay, while nearly one in five (18%) said Mr Trump made them more likely to vote out compared to 12% who said the opposite.
The ERS is calling for a review to ensure future referendums do not repeat the same mistakes.
It makes nine recommendations, including tasking an official public body to intervene when misleading claims are made by the campaigns, and asking Ofcom to conduct a review into an appropriate role for broadcasters to play in referendums.
It also wants votes extended to all 16-year-olds and the early publication of a definitive rule book to govern campaign conduct, followed by a minimum six-month regulated campaign period.
The society wants to bolster public involvement by creating a citizens' panel tasked with pre-legislative scrutiny of any referendum bill and the allocation of publicly funded resources to stimulate citizen-led debates and deliberation.
Stephen Gethins, the SNP's Europe spokesman, said: "The SNP welcomes this report which highlights the serious democratic deficiencies of the EU referendum – concerns that we raised repeatedly before and during the campaign but which the UK Government chose to ignore."