People may feel less unethical about sharing misinformation on social media if they repeatedly encounter the fake news item, even when they don't believe it, according to a study involving more than 2,500 people.
The researchers, including one of Indian Origin -- Medha Raj from the University of Southern California in the US -- said seeing a fake headline just once leads individuals to temper their disapproval of the misinformation when they see it a second, third, or fourth time.
As part of the study, published in the journal Psychological Science, the researchers asked online survey participants to rate how unethical or acceptable they thought it was to publish a fake headline, and the likelihood that they would "like", share, and block or unfollow the person who posted it.
They found that the participants rated headlines they had seen more than once as less unethical to publish than headlines they saw for the first time.
The participants also said they were more likely to "like" and share a previously seen headline, and less likely to block or unfollow the person who posted it, according to the study.
However, they did not rate a previously seen headline as significantly more accurate than new ones.
More From This Section
So the main results cannot be explained by a tendency to misremember false headlines as true, the researchers said.
The team also noted that efforts used by social media companies to curtail misinformation mainly focussed on helping people distinguish fact from fiction.
They quoted the example of Facebook which has tried informing users when they try to share news that fact-checkers have flagged as false.
The researchers cautioned that such strategies may fail if users feel more comfortable sharing misinformation they know is fake when they have seen it before.
According to the scientists, repeating misinformation gives it a "ring of truthfulness" which can increase people's tendency to give it a moral pass, irrespective of whether they believe it.
Merely imagining misinformation as if it were true can have a similar effect, they said.
"The results should be of interest to citizens of contemporary democracies. Misinformation can stoke political polarization and undermine democracy, so it is important for people to understand when and why it spreads," said study co-author Daniel Effron from London Business School in the UK.