Wednesday’s top story: Cohen to give explosive testimony on Trump campaign and WikiLeaks. Plus, the surgeons saving Instagram’s favourite dogs

Good morning, I’m Tim Walker with today’s essential stories.

Cohen to call Trump a ‘racist’ and ‘conman’ at public hearing

Michael Cohen is set to describe his former boss Donald Trump as a “racist”, a “cheat” and a “conman” in prepared remarks at the opening of his public testimony to the House oversight committee on Wednesday. The president’s former lawyer also intends to make the bombshell claim that he witnessed Trump speaking to the adviser Roger Stone about Stone’s contacts with WikiLeaks during the 2016 presidential campaign – and that Stone told Trump of WikiLeaks’ plan to publish emails stolen from the Democratic National Committee and Hillary Clinton’s campaign.

Key claims. Josephine Tovey breaks down the most explosive extracts from Cohen’s prepared testimony, including details of the Moscow Trump Tower project, his payoff to the adult film star Stormy Daniels and Trump’s private racism.

House Democrats unveil Medicare for All bill

Facebook Twitter Pinterest Senator Bernie Sanders speaks with other Democrats during their previous attempt to introduce a ‘Medicare for All Act’ in 2017. Photograph: Yuri Gripas/Reuters

House Democrats are making an ambitious new attempt to overhaul US healthcare by introducing the Medicare for All Act of 2019 on Wednesday. Once embraced only by the party’s left wing and promoted by Senator Bernie Sanders during his 2016 presidential run, the idea of Medicare for All is now close to being Democratic orthodoxy. The plan will, for the first time, be subject to congressional hearings, despite having no chance of passing the GOP-controlled Senate.

Emergency blocked. The House has passed a resolution to revoke Trump’s national emergency declaration, to block the president from funding a border wall without congressional approval. Several Senate Republicans have indicated they may vote for the resolution, which would mark a direct challenge to the president’s power from his own party.

Pioneering ex-minister to testify over Canada scandal

Facebook Twitter Pinterest Jody Wilson-Raybould with Justin Trudeau during her swearing-in ceremony in 2015. Photograph: Adrian Wyld/AFP/Getty Images

Jody Wilson-Raybould, who was Canada’s first indigenous attorney general, will testify to the Canadian parliament’s justice committee on Wednesday, addressing in public for the first time allegations that she was pressured to drop prosecutions targeting a major engineering firm by aides from the office of the prime minister, Justin Trudeau. The pioneering former minister of justice was demoted to the role of veterans affairs minister last year and resigned from the cabinet earlier this month.

Election year. The growing scandal comes as Trudeau prepares for a federal election in October, where he will face Jagmeet Singh of the New Democratic party, whose byelection win this week has cemented his position as the first non-white leader of a major party in Canada.

Plastic waste found even in the world’s deepest waters

Facebook Twitter Pinterest A green turtle eats a plastic bag resembling a jellyfish. Photograph: Alamy

Plastic waste is contaminating the Mariana Trench and at least five more of the deepest spots on Earth, scientists have found, concluding in a study that “it is highly likely there are no marine ecosystems left that are not impacted by plastic pollution”. The researchers found evidence of microplastic ingestion by organisms even at depths of more than 6,000 metres, suggesting the problem of plastic waste is far more profound than was previously known.

Reproductive problems. In shallower waters and on land, plastics are being blamed for reproductive problems among wildlife. Another report found, for example, an orca pod facing high levels of pollutants that has failed to produce a single calf in 25 years.

Crib sheet

Donald Trump and Kim Jong-un have arrived in Vietnam for their Hanoi summit , set to begin on Wednesday. Julian Borger explains the stakes of the meeting, which you can follow via the Guardian’s live blog.

Pakistan says it has shot down two Indian jets as hostilities between the two nuclear-armed neighbours escalated on either side of their disputed border in Kashmir . India has yet to confirm the claims.

The FBI is struggling to attract new recruits, according to a report by the Wall Street Journal, which said the number of applicants for special agent positions had plummeted from 68,500 in 2009 to just 11,500 last year.

Eight rescuers including firefighters have taken part in the rescue of an overweight rat from a sewer grate in Bensheim, Germany, where the fat rodent had got stuck after piling on the ounces over the winter.

Must-reads

Facebook Twitter Pinterest A dog awaits surgery in the operating theatre at Battersea Dogs & Cats home in London. Photograph: Jill Mead/The Guardian

The surgeons keeping pugs and bulldogs alive

They may look cute on Instagram, but flat-faced dogs are prone to serious breathing problems, and more and more are undergoing surgery to save their lives. Simon Usborne steps into the operating theatre to see the gory results of an unchecked pet trend.

The Grand Canyon ranger who’s older than the park

Rose Torphy is 103 years old: three years older than the Grand Canyon national park, which is celebrating its centenary in 2019 and where she was recently sworn in as a junior park ranger. The canyon is “the most marvelous thing”, she tells Eric Lutz.

Behind a landmark documentary about Apollo 11

Half a century after humans first went to the moon, the film-maker Todd Douglas Miller has worked with Nasa to restore remarkable unseen footage from the Apollo 11 mission. The result, says Adrian Horton, is this year’s first must-see documentary.

The artist collecting America’s neighbourhood murals

Camilo Jose Vergara, the Chilean-born photographer and MacArthur Fellow, has spent four decades travelling the US, photographing the work of anonymous local muralists and street artists in poor, segregated communities.

Opinion

The world is waking up to the unchecked power of Big Tech. But to truly enfranchise those excluded from the digital economy, says Evgeny Morozov, the left must think more radically than the neoliberals and technocrats who currently represent them.

How could digital technologies help redesign core political institutions, including representative democracy and its bureaucratic apparatus, and make them more decentralized and participatory?

Sport

It’s 100 days until the Women’s World Cup kicks off in France on 7 June. As Team USA prepare to defend their title, Louise Taylor tells you everything you need to know about the tournament.

With MLS returning this weekend, the Guardian’s soccer writers make their predictions for the season, which ought to be a big one for former European stars Wayne Rooney and Zlatan Ibrahimović.

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