Pets trained to bite, hold and release on command are growing ever more popular in the UK. But why – and at what cost to the animals and their owners?

Even if you’re not afraid of dogs, you might be a little intimidated by Butch Cassidy. His tail may be wagging, but the Belgian shepherd weighs 40kg and moves with awesome agility. Even a casual brush of his body could knock you off your feet if you weren’t expecting it. “I don’t for a minute think he’s going to bite anyone,” said his owner Grahame Green earlier. “Although he would, if I asked him to.” Now Green’s about to demonstrate.

He brings Cassidy to heel, and gets him to sit. Facing them is another man, Florin, already braced and wearing a protective arm sleeve. The dog is visibly quivering with excitement, so keen is his anticipation for what comes next. Green gives a one-word command, in German. Cassidy darts forward, an auburn arrow, and in that split-second clamps on to Florin’s forearm. Florin is engaging every muscle to remain upright, but Cassidy does not let go until Green gives the word.

Netflix film revisits evidence that led to Letby’s conviction and hears from expert who says his research was misused

Shortly after Lucy Letby was sentenced to 15 whole-life terms for murdering seven infants and attempting to murder seven others between June 2015 and June 2016 – a conviction that made her Britain’s worst ever child serial killer – Cheshire police agreed to give “unparalleled and exclusive access” to the makers of a Netflix film about the case.

The finished documentary, The Investigation Of Lucy Letby, which is released on Wednesday, must be very different from what the producers envisaged when they first began work on the project, given the subsequent unexpected turns in the story. Since the two trials, the prosecution evidence and police handling of the case have faced criticism from an unprecedentedly large number of distinguished British and international medical experts. Led by the Canadian neonatologist, Dr Shoo Lee – who says again in the feature-length Netflix documentary that his research was misused to convict the nurse – many of the experts are convinced Letby is innocent, the victim of a catastrophic miscarriage of justice.

Moves to ban under-16s from social media should raise deeper questions about who controls democracy’s digital infrastructure

The last UK general election of the 20th century was also the first to anticipate, albeit faintly, the coming technological revolution. The 1997 Labour and Conservative manifestos both included pledges to connect schools to something they called “the information superhighway”.

That metaphor soon fell out of use, unmourned, although it contains an interesting policy implication. Roads need rules to prevent accidents. Superhighways do not sound like the kind of places where children should play.

Rafael Behr is a Guardian columnist

Guardian Newsroom: Can Labour come back from the brink? On Monday 30 April, ahead of May elections join Gaby Hinsliff, Zoe Williams, Polly Toynbee and Rafael Behr as they discuss how much of a threat is Labour from both the Green party and Reform and whether Keir Starmer can survive as leader of the Labour party? Book tickets here or at guardian.live

When Essex University’s Southend campus opened, it was a message of hope for a ‘left behind’ UK seaside town. Its closure will be felt far beyond its 800 students, some of whom will not get their degrees

The seaside city of Southend-on-Sea, on England’s east coast, looks grey on a winter afternoon in term-time. Its cobbled high street, bordering the university campus, is sparsely populated with market stalls, vape shops and discount retailers, and feels unusually quiet.

“There used to be lots of shops, restaurants and youth clubs around here,” says 23-year-old Nathan Doucette-Chiddicks. Now, the city is about to lose something else that it can scarcely do without.

League’s star said to be unhappy over his club’s transfer dealings and Karim Benzema’s move. Now he could face his first backlash

Jurassic Park sounded great given the spectacular beasts on display, but there was chaos after they started to do their own thing. When Cristiano Ronaldo, surely the T rex, and Karim Benzema, perhaps a velociraptor, are scoring in spectacular fashion there are headlines around the world, but the Saudi Pro League is finding out that when they start to flex their muscles off the pitch, there is even more interest and, it turns out, a real problem for the competition.

What happened on a manic Monday in the SPL should have been about what unfolded on the pitch. Al-Hilal, in first, drew with third-placed Al-Ahli. Al-Nassr won, to stay second, closing to within a point of the leaders. If Brendan Rodgers, having a whale of a time with Al-Qadsiah, wins his game in hand then four points will separate the top four with just over a third of the season remaining. It is the kind of title race most leagues would love.

Despite Trump-appeasing shows of willingness, a big gap remains between the positions of delegations meeting in Abu Dhabi

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Senior Ukrainian and Russian officials are due to meet in Abu Dhabi for a second round of talks brokered by the Trump administration.

The two-day talks are expected to mirror last month’s format, with negotiators from Washington, Kyiv and Moscow in attendance.

Epstein files appear to show then business secretary passing market sensitive information to child sex offender

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The Metropolitan police have formally launched a criminal investigation into allegations that Peter Mandelson leaked Downing Street emails and market sensitive information to the child sex offender Jeffrey Epstein.

Documents from the Epstein files released in recent days appeared to show the then business secretary sent confidential details of internal discussions to the late financier in the aftermath of the financial crash.

Exclusive: Police say they will review allegation that Epstein sent woman to UK to have sex with Andrew at Royal Lodge, his former home

British police are to review fresh allegations that Jeffrey Epstein provided Andrew Mountbatten-Windsor with a woman to have sex with at the Royal Lodge in 2010, as it emerged that the former prince had moved out of his home.

The woman has claimed she spent the night at the then prince’s residence in Windsor, her US lawyer, Brad Edwards, said after the allegations surfaced over the weekend. The woman, who is not British, was in her 20s at the time, and was later given a tour of Buckingham Palace, it is further alleged.

Billionaires and intellectuals attended events with the disgraced financier years after he served time for sex offense, files reveal

Newly released emails and travel itineraries appear to show that for years after Jeffrey Epstein served time for procuring underage girls for prostitution, he continued to attend exclusive dinners alongside Silicon Valley’s most famous billionaires.

The emails, part of a trove released by the Department of Justice on Friday, show that as late as 2018, Epstein was invited to or attended dinners alongside the likes of Elon Musk, Jeff Bezos, Google founders Larry Page and Sergey Brin, Twitter co-founder Evan Williams, Microsoft founder Bill Gates, and Google vice-president and later Yahoo CEO Marissa Mayer.

Latest communications undermine Chomsky’s earlier claims that he primarily had financial dealings with Epstein

The close friendship that Noam Chomsky maintained with Jeffrey Epstein continued being detailed extensively among millions of investigative records pertaining to the late convicted sex offender recently released by the US justice department, including Chomsky “fantasizing about the Caribbean island”.

In Friday’s tranche of documents, which built upon earlier disclosures of their close social ties, there is no specific indication that the famed academic and linguist was referring to his friend’s private Caribbean island where children were sexually abused. But the personal familiarity between the two men in that exchange is palpable, as it is in numerous other emails between Chomsky and Epstein aimed at planning more mundane social gatherings.