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Q: By Marianna SpringSpecialist disinformation reporter, BBC News The adverts show the Democratic Party challenger with an earpiece, and say that he refused to have his ears checked for devices prior to the debate. The Biden campaign rejected the claims. The Trump campaign adverts ask: "Why won't Sleepy Joe commit to an ear test?" and "Who is in Joe's ear?" Accusations that presidential candidates have received debate help via hidden hearing devices are familiar, albeit unproven. Such allegations have been levelled against both Republican and Democratic candidates in the past. Prior to Tuesday's debate, the rumour about Mr Biden's supposed earpiece was circulating on several social networks, and was being promoted by the Trump campaign. At least 15 versions The advertising campaign was launched after the debate, and also promotes two other baseless but widely shared rumours about Mr Biden. One suggested he asked for breaks during the debate, and another accused him of refusing a "drug test". The photo featured in the advert is not from Tuesday's debate. It was first shared online in September 2019. In a number of the adverts, it has been doctored to show Mr Biden wearing wireless Apple headphones. This was not the case in the original image. Some versions circle the ear featuring the headphone. By Wednesday evening, there were at least 15 different versions of the advert, and according to Facebook's Ad Library, they had reached at least 10 million users. Facebook has pledged to label posts containing voting misinformation and point users towards accurate information ahead of the election. However its policy does not involve fact-checking political speech, including in advertisements. The company declined to comment about the latest Trump ad campaign. Rumour origins Hours before the debate, the claims went viral on Facebook and YouTube. Identical memes were pushed by a number of popular Facebook pages with names such as US Conservative and Unhinged Left. They claimed "Joe Biden should be inspected for a hidden earpiece as well as submit to a drug test before the debate". These memes are subject to fact-checks - and some have had warning labels applied to them on Facebook. The claims were picked up by Fox News and other conservative news outlets. They were further amplified by supporters of QAnon, an unfounded a conspiracy theory that claims President Trump is fighting a secret war against elite Satan-worshipping paedophiles. Those who believe in QAnon are known for promoting political disinformation on social media which targets opponents of the president. They shared close-up pictures of Mr Biden's ears, alleging a listening device was visible. During the debate, some also shared photos of a fold in Mr Biden's shirt, claiming it was caused by a wire, and of a supposed device on his wrist, where he wears a rosary in memory of his late son Beau. Nothing new Conspiracy theories about secret listening devices have been recycled in presidential election campaigns for the past two decades. Democratic candidate Hillary Clinton faced similar unfounded claims ahead of the 2016 presidential election. In 2004, rumours circulated among left-wing sites and blogs that President George W Bush was being aided by a secret earpiece. None of those allegations were found to be true. Even if a candidate did wear an earpiece, any advantage would be questionable. As TV and radio presenters can attest, listening to someone while simultaneously talking during the back-and-forth of a live event is a difficult skill to master.
A: US President Donald Trump's re-election campaign is running hundreds of Facebook advertisements pushing an unfounded conspiracy theory that Joe Biden cheated during the first US presidential debate.
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Q: Mario Cerciello Rega, 35, was stabbed to death last July as he investigated a drug deal gone wrong in central Rome. Californian students Finnegan Lee Elder and Gabriel Christian Natale-Hjorth face life sentences if convicted. The US students say they were acting in self-defence, believing the two officers - who they say did not identify themselves - were criminals. Rega's murder received huge amounts of attention in Italy. He had only just returned to duty from his honeymoon, and huge crowds turned out for his funeral at the same church where was married just 43 days before. But there have also been questions about how the case has been handled. How did Rega die? Mr Elder and Mr Natale-Hjorth - both teenagers at the time - were allegedly trying to buy cocaine last summer in the Trastevere area, near to Vatican City. Investigators said a man named Sergio Brugiatelli helped the pair find a dealer. But the students were allegedly sold crushed aspirin instead of drugs. Both men then are said to have taken Mr Brugiatelli's rucksack, and demanded their money back and a gram of cocaine in exchange. At this point, Mr Brugiatelli allegedly rang the police. Undercover officers Rega and his partner, Andrea Varriale, arrived soon after. During the ensuing brawl Rega was stabbed 11 times with an 18cm (7 inch) blade. Police said they later found the weapon hidden behind a false panel in the US students' hotel room. Mr Elder has admitted stabbing the officer. But both he and Mr Natale-Hjorth stand accused of murdering Rega, and are also facing extortion charges. How has the case been handled? There have been a number of questions raised about the case in both the Italian and US media. A leaked photo showing Mr Natale-Hjorth blindfolded and restrained at a police station appeared in the press shortly after their arrest. Rega's partner Mr Varriale later said he had filmed Mr Natale-Hjorth's interrogation on his phone, which is where the photo came from. The police officer said he and Rega identified themselves on the night. But the US students say they saw no evidence they were police. And Mr Varriale also faced a "dereliction of duty" charge for not carrying his weapon on the night. Neither he nor Rega were armed, which is against procedure. Defence lawyers for the US students have also raised questions about the case. Talks between Mr Elder and his lawyer appeared in the Italian media which suggested he had confessed. But the defence said the transcripts were badly translated and seemed to omit parts of their conversation. Some in the US have even compared the case to that of Amanda Knox. The US student served four years in prison for the murder of Meredith Kercher. Italy's top appeals court overturned her conviction in 2015.
A:
Two US students accused of murdering a police officer have appeared in court in Italy at the start of their trial.