But that didn't stop news outlets, including the American broadcast network CBS, reporting the story.
Only the Detroit Free Press was able to debunk the rumour, several hours after the story had 'broken' online, by calling the state police department spokesperson to verify the claim.
"He [the spokesperson] said no, the Batmobile is still in the Batcave," said John Esslin, a reporter at The Record in New Jersey, speaking at the Society of Professional Journalists Region 9 Conference in Denver.
"So that story was bogus, false, not true – but viral."
The Batmobile story, said Esslin, was a good example of some of the "ethical quandaries" some journalists have found themselves in due to the perceived importance of being the first to break a story.
Instead, he said, journalists should advocate what he called "slow journalism".
Slow journalism is a developing trend in news, with publications such as Delayed Gratification focusing on the in-depth explanations and context behind the stories in the headlines, rather than breaking news.
However, Esslin used the term to encourage journalists to take steps to verify and fact-check stories, especially those sourced from social media, before publishing.
This is particularly important when it comes to social media where an inaccurate post can spread like wildfire thanks to retweets and shares from people who presume the information is correct, coming as it does from an official news source.
"I'm not talking about blowing deadlines. I'm not talking about missing your marks. I'm not talking about not covering breaking news in a timely fashion," Esslin said.
"When I say I'm advocating for slow journalism I'm advocating in the sense of what the Detroit Free Press did, which is take the time, make the call, check the facts."
However, he noted that an exception for breaking news, when there is more urgency in reporting information emerging from social media and user-generated content.
In these instances, journalists should always state where information is unconfirmed, and "be transparent in terms of telling readers what is known and what is unknown".
Esslin also cautioned against retweeting information from social media without proper verification.
"When it comes to our social media footprint, let's be careful where we step," he said, "and let's take our time in getting there".
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