There are several metrics essential to a free and functioning democracy. One is freedom of the press. Another is the guarantee of fair elections. This week Turkish president Recep Tayyip Erdogan underlined his country’s increasing authoritarianism with the announcement that Istanbul’s mayoral election will be held again. Erdogan’s Justice and Development Party (AKP) narrowly lost the election in the country’s largest city and the president’s home town in April. Authorities have now announced that the ballot will be re-run, citing voting irregularities. Erdogan, now in power for 16 years, first as prime minister and then as president following a constitutional amendment in 2017, welcomed the move as “an important step to strengthen our democracy”. The news provoked outrage from the EU among others.

But the promise of free and fair elections in western democracies is not as secure as it once was. In recent days, President Donald Trump has revived concerns about his commitment to some of the basic norms of the American electoral system.

Last weekend, he tweeted that despite his “tremendous success” as president, Democrats had “stolen two years of my (our Presidency) . . . that we will never be able to get back. The Witch Hunt is over but we will never forget,” he said, referring to the Mueller investigation which concluded in March. But it was a retweet that raised alarm bells.

The suggestion that Trump’s term could be extended sparked unease in many quarters

The president posted a tweet by Jerry Falwell, a prominent evangelical preacher and a Trump supporter. Noting the “soaring” economy and repeating Trump’s mantra of “no obstruction, no collusion”, he tweeted: “I now support reparations – Trump should have 2 yrs added to his 1st term as payback for time stolen by this corrupt failed coup.” Aside from the provocative use of the term “reparations” – America is in the midst of a debate about whether to pay reparations to the descendants of slaves – the suggestion that Trump’s term could be extended sparked unease in many quarters.

‘Poisoning’ public mind

Was the president serious? House speaker Nancy Pelosi for one believes there is cause for concern. In a weekend interview she said she believed Trump might not voluntarily leave the White House if the Democrats do not win by a big margin in the 2020 election.

“If we win by four seats, by a thousand votes each, he’s not going to respect the election,” she said. “He would poison the public mind. He would challenge each of the races; he would say you can’t seat these people.” It was a point raised by Trump’s former attorney Michael Cohen – who began a three-year prison term this week – in testimony to Congress in February. “I fear that if he loses the election in 2020, that there will never be a peaceful transition of power,” he said.

'I fear that if he loses the election in 2020, there will never be a peaceful transition of power'

But even if the president is unlikely to resist the outcome of the next election, he is sowing distrust about the US electoral system. Trump has a history of discrediting the integrity of America’s democracy. Shortly after winning the 2016 presidential election, he claimed he had also won the popular vote. “In addition to winning the Electoral College in a landslide, I won the popular vote if you deduct the millions of people who voted illegally,” he tweeted. In particular he has singled out California, claiming that “millions and millions” of people have voted illegally. On assuming office, he set up a commission to investigate voter fraud. But it was soon abandoned – while the White House blamed states for not handing over voter data, many suspected that it had simply found insufficient evidence.

Analysis has in fact found that illegal voting is rare. A study by Loyola Law School professor Justin Levitt found 31 instances of voter fraud between 2000 and 2014 of a total of one billion votes. A report by the justice department under then president George W Bush came to similar conclusions.

What is a problem in the United States, however, is voter suppression – usually of African-American and minority voters.

Acts of gerrymandering

The US is grappling with egregious instances of gerrymandering in states including Michigan, North Carolina, Pennsylvania and Wisconsin, raising questions about the integrity of the voting system.

In North Carolina, for example, an inventive redrawing of electoral boundaries by a Republican-controlled state legislature had its desired effect. Though about half of voters backed Democratic candidates in the 2016 elections, Republicans won 10 of the state’s 13 House seats. Democrats similarly stand accused of designing electoral boundaries in Maryland to favour their own party. The issue is due before the US supreme court this year.

Voter representation is likely to feature in the 2020 elections. Presidential hopeful Kamala Harris has already called for change, arguing that people should be automatically registered to vote.

Stacey Abrams, who narrowly lost the gubernatorial race in Georgia last year amid allegations of voter suppression, has formed a non-profit group dedicated to increasing voter access.

Former president Barack Obama has thrown his support behind the National Democratic Redistricting Committee – an association chaired by former attorney general Eric Holder which aims to address the issues of redistricting and voter participation.

In addition, the Trump administration is facing questions about its proposal to add a citizenship question to the 2020 census, a move that some suspect is designed to depress the Democratic vote.

Donald Trump’s retweet this week may at best be a tongue-in-cheek comment but the president’s continual undermining of the voting system is alarming, particularly given that he has refused to accept the findings of his own intelligence services that Russia tried to interfere in the 2016 presidential election. Preserving the health of the American voting system should be a concern to all Americans, not least the president of the United States.

Suzanne Lynch is Washington Correspondent