Facebook and Google should temporarily halt political advertising on their platforms to help prevent the spread of disinformation ahead of the UK General Election on December 12, say Mozilla, privacy campaigners, academics and others.
In an open letter addressed to Facebook's Mark Zuckerberg (CEO) and Nick Clegg (VP of global affairs and communications), and Google's Sundar Pichai (CEO) and Kent Walker (senior vice president for global affairs and chief legal officer), researchers, technologists and digital rights activists have voiced their concerns about online political advertising.
They say a moratorium -- a temporary prohibition -- should be put on political and issue-based advertising until the UK Parliamentary elections have concluded.
"This moratorium would come at a watershed moment: Disinformation thrives online ahead of elections. Meanwhile, both Facebook and Google's ad transparency tools have proven to be flawed. As a result, right now -- when it matters most -- UK citizens cannot trust the information they are encountering online," the letter says.
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The letter -- signed by senior figures at Mozilla, Demos, Doteveryone, the Institute for Strategic Dialogue, the Open Data Institute, Tech Inquiry and the University of Sheffield -- voices particular concern about Mark Zuckerberg's recent attempt to justify allowing politicians to lie in political adverts on Facebook.
It also follows Twitter's decision to ban political adverts on its platform from mid-November.
While the the UK Electoral Commission, Information Commissioner and the DCMS parliamentary Select Committee have all called for legislation to help address the issues around online advertising and disinformation, the imminent suspension of parliament means there will be no time to pass laws.
This, the letter warns, will create a "legislative blackspot", allowing politicians to openly publish disinformation. Mozilla and its allies have also voiced concerns about a lack of transparency in online advertising and how Google and Facebook are allowing personal data to be used to target adverts against individuals.
"As we prepare to enter purdah, and without proper legislation, we're calling on you to take a stand and issue an immediate moratorium on all political and issue-based advertising on your platforms until the conclusion of the UK Parliamentary Elections on the 12th of December," the letter asks.
The open letter points out that this isn't without precedent: in last year's Irish referendum on abortion rights, Google blocked political advertising for two weeks ahead of polling day, while in the Israeli and Canadian elections, political adverts were blocked during the election period.
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Mozilla's letter accepts that blocking political adverts isn't a long-term solution, and that in the short-term it could harm smaller campaign groups, but it argues that in order to prevent the spread of disinformation in the UK general election, temporary action needs to be taken.
"But in the UK context, with dated electoral law and a lack of implementation of existing data protection laws, coupled with your platform's failures to sufficiently address the concerns raised, in this instance, it's a necessary trade-off," the letter says.
Facebook and Google are asked to take action now in order to allow candidates and parties to plan their campaigns without the use of the two online platforms.
The letter comes shortly after Facebook dropped an appeal and agreed to pay a £500,000 fine issued to it by the Information Commissioner's Office after an investigation into the misuse of personal data in political campaigns, which came to light as part of the Cambridge Analytica scandal.