There was a lack of consistency in how political and "issues-based" advertising was defined during the 2019 European Election, according to a report on online political advertising.
The report was commissioned by the Broadcasting Authority of Ireland and carried out by researchers at Dublin City University.
Researchers from the Institute for Future Media and Journalism at DCU examined political advertising on Facebook, Twitter and Google during the 2019 European election campaign, in the context of the European Commission's 'Code of Practice on Disinformation', which is self-regulatory and designed to address the spread of online disinformation and "fake news".
More than 1,500 political adverts were monitored for issues including whether the ad was paid for and who paid for it, did it carry a disclaimer that it was a political or issues-based ad, and information on micro-targeting.
The report found that while some relevant information could be gathered, it was not possible to arrive at a clear, fully comprehensive picture of the nature and scale of the political advertising on the three platforms.
FUJO Director Jane Suiter said "Online advertising offers an effective means of reaching target audiences so it is unsurprising that it is now integral to any modern, political campaign.
"However, the lack of transparency presents significant risks and challenges and could potentially undermine the integrity of the electoral process.
"Our findings indicate that the digital platforms have much room for improvement if they are to comply with their commitments under the Code of Practice on Disinformation."
BAI CEO Michael O'Keeffe said that the three platforms actively engaged with their commitments to support electoral transparency, but said there was a lack of consistency from platform to platform on how they presented the data and how political and issues based advertising was defined.