With Michael Bloomberg now running for president, the news service that bears his name has said it will not 'investigate' him or any of his Democratic rivals but will continue investigative coverage of President Donald Trump's administration.

Bloomberg Editor-in-Chief John Micklethwait announced the new guidelines for presidential campaign coverage in a note to the $22.5billion news organization's 2,700 journalists and analysts on Sunday, shortly after the former New York City mayor announced his candidacy.

'There is no point in trying to claim that covering this presidential campaign will be easy for a newsroom that has built up its reputation for independence in part by not writing about ourselves,' Micklethwait wrote.

He said that the organization will continue its tradition of not investigating Bloomberg, or his family and foundation, and will extend that policy to his rivals in the Democratic primary out of fairness.

That policy will not be applied to the Trump administration as it is 'the government of the day'. Investigative coverage of Trump will be reassessed should Bloomberg be picked as the Democratic candidate for president next fall, Micklethwait said.

With Michael Bloomberg now running for president, the news service that bears his name has said it will not 'investigate' him or any of his Democratic rivals (file photo)

Bloomberg will continue its investigative coverage of President Donald Trump's administration 'as the government of the day'. That coverage of Trump will be reassessed should Michael Bloomberg be picked as the Democratic candidate for president next fall

Micklethwait acknowledged that the company has entered uncharted territory as 'no previous presidential candidate has ever owned a journalistic organization of this size' - and said that the new policies are not an 'exhaustive rulebook' but rather a set of 'basic principles'.

The largest changes will be instituted within Bloomberg Opinion, as the candidate has historically had the most contact with and influence over that department, Micklethwait said.

Executive editors David Shipley and Tim O'Brien will both be taking leaves of absence to join Bloomberg's campaign, along with other members of the Editorial Board.

The Board itself will be suspended in their absence, meaning that the company will not run unsigned editorials, since they usually reflected Bloomberg's point of view.

The organization will continue to run opinions by columnists and some columns from outsiders, although none of the latter will be about the campaign.

Bloomberg Editor-in-Chief John Micklethwait announced the new rules in a note to his news organization's 2,700 journalists and analysts Sunday, shortly after the former New York City mayor announced his candidacy

Bloomberg started his news service in 1990 to complement the financial information he sold to customers. It has since expanded, with its news available in many formats, including a television and radio network and Bloomberg Businessweek magazine.

The entry of Bloomberg into the presidential race also raises potential conflict-of-interest questions involving his extensive business holdings, which go well beyond his news service. Bloomberg's businesses, which include selling financial data services, employ more than 19,000 people in 69 countries.

Experts say those holdings could create financial conflicts stemming from Bloomberg's policy positions, both domestic and foreign, unless he takes decisive action to formally remove himself from his businesses.

'We want people to have confidence that folks in government, including the president, are acting out of a sense of concern for the public interest, not the vision of what their private interests are,' said Kathleen Clark, a law professor at Washington University in St. Louis who focuses on legal and government ethics.

Every president since Jimmy Carter has acted to sell assets that could create conflicts of interest, Clark said — except President Trump, who has provoked broad criticism for remaining financially connected to his businesses.

Senior advisers for Bloomberg did not immediately answer questions Sunday about whether he would create a firewall of some sort between himself and his many entities, including his foundation based in Manhattan.

When asked about potential conflicts of interest when he was considering a run earlier in the year, Bloomberg had pledged to 'separate myself' from his foundation and private businesses should he launch a campaign.

On Sunday, though, it was unclear whether he was still committed to doing so and how specifically he might separate himself from his many business interests.

At his news service, Micklethwait said, Bloomberg reporters will still cover polls, policies and how the Bloomberg campaign is faring, much as it does for all candidates.

If other credible news organizations do investigative stories on Bloomberg or other Democrats, the news service will summarize them or publish them in full, he said.

'We will not hide them,' Micklethwait said.

To anyone who thinks the news service shouldn't cover Bloomberg at all, he said Bloomberg News 'has handled these conflicts before — and proved our independence.'

The situation presents an ethical tightrope. When Bloomberg was considering a candidacy in 2016, the news service's politics news director in Washington, Kathy Kiely, quit and said she did not feel she could do her job without covering Bloomberg aggressively.

Kiely said Sunday that the new rules 'relegate his political writers to stenography journalism ... it's not satisfying for journalists and it's not satisfying for readers. I think people will go elsewhere for in-depth political coverage.'

Kiely said Michael Bloomberg should step completely away from his news organization and let it operate independently. Instead, he's undermining the news organization 'he worked so hard and spent so much money to build up.'

It's good that the news service has a structure in place to consider issues as they arise, said Kelly McBride, senior vice president at Poynter and chair of the Craig Newmark Center for Ethics and Leadership. But every day they will have to consider tough decisions about how to cover the candidacy, she said.

'I can't imagine that they're not going to have to deal with the temptation of self-censorship,' she said.

Bloomberg Opinion Executive Editor Tim O'Brien (left) and Senior Executive Editor David Shipley have announced that they, along with some members of the editorial board, would be taking a leave of absence to join their CEO's campaign

Chief Content Officer Marty Schenker has been asked to oversee the campaign coverage during Bloomberg's run.

'This is a structure that can cope with many eventualities,' Micklethwait wrote. 'No doubt, many of you are already thinking of possible complexities that may raise. My response is: let's get back to work. We can spend a long time debating 'what ifs.' I would rather that we got on with the journalism and let the work speak for itself.'

Regarding his business interests, Bloomberg should make a clear decision right away, said Richard Painter, a professor at University of Minnesota Law School. Painter served as chief White House lawyer for ethics under President George W. Bush from 2005 to 2007.

Bloomberg should divest heavily from his businesses, Painter said.

'He needs to pledge that if he's elected president, basically all his companies get sold,' he said, adding that should include changing the governance of Bloomberg's charitable foundation.

It's a different conversation than when he served as mayor of New York, Painter said.

'The mayor of New York doesn't regulate the financial industry,' he said.

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