The leaders of the trade union for journalists have issued a warning over attempts to intimidate the media ahead of the SNP's unveiling their manifesto today.

Their interventions come weeks after SNP members heckled and laughed at the BBCs Scotland editor James Cook when he asked John Swinney a question about independence at the party's general election campaign launch in Glasgow earlier this month. 

The First Minister intervened and asked members of his party neither to heckle or cheer journalists who were asking him questions.

His comments followed repeated criticisms of the media by SNP figures and candidates from the platform ahead of his speech, aimed to get the party's campaign fully underway on June 2.

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Speaking ahead of the SNP's manifesto launch today, Michelle Stanistreet, general secretary of the National Union of Journalists (NUJ) told The Herald: “Journalists reporting at general election events, carrying out their work and scrutinising party policies, shouldn’t have to contend with being heckled or abused simply for doing their job.

"The whole point of a manifesto process is about enabling the public to be as informed as possible on wide-ranging policies that influence their voting decisions. Journalists play a vital role in that process and in our democracy. I would expect all party leaders to ensure that reporters are free to carry out their work professionally and with dignity.”

(Image: PA) BBC Scotland editor James Cook was heckled by SNP members at their party's general election campaign launch.  Photo PA.

Nick McGowan-Lowe, the NUJ's Scotland organiser, added: "This looks to be one of the most crucial Westminster elections in decades – and all political parties and their supporters must accept that journalists play a crucial part in the democratic process by asking hard questions of both those politicians who seek power, and those who may be risking losing it.  

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"The workplace of our members is not just their newsrooms, but the pavements, podiums and photocalls, and everyone deserves to work without abuse or intimidation."

The controversy erupted on June 2, when during a question and answer session after the First Minister's address, Mr Cook asked Mr Swinney about the cost of independence citing concerns raised by the SNP over the cost of the UK leaving the EU.

Mr Cook pointed out that the UK was in the EU for a much shorter period that Scotland has been in the UK.

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His question provoked a number of activists at the event booing the reporter, with one member shouting at him “get yourself out of here”.

Mr Swinney then intervened telling party members: “Before we go any further, I just said I believe in open debate and respect. 

“So, for this bit of the gathering, no questions are to be applauded or heckled, and none of my answers are to be applauded or heckled. So, fair rules for everybody. James, could you start again please and you’ll be heard in silence.”

Mr Cook then asked his question again: “You’ve said that leaving a 50-year-old union with the EU has wiped billions from the economy. Why would leaving a 300-year union with England not be worse?”

Mr Swinney responded: “What independence enables us to do is to take decisions that are important and relevant to enhancing the lives of people in Scotland.”

His appeal to party members to show respect to journalists came after several of the SNP’s election candidates and senior figures had earlier criticised the media.

During his speech Stewart Hosie, the SNP campaign director, told the hall: “It is worth reminding ourselves no matter occasionally what the media might say, not only do we remain Scotland’s largest political party by a mile, we are larger than all of our opponents combined.”

Activist Charlotte Armitage then went on to hit out at “bias media” for the SNP being excluded from TV debates between Keir Starmer and Rishi Sunak.

Then the SNP’s candidate for Dunfermline and Dollar, Naz Anis-Miah, took another pot shot at the media saying rival parties had a “lot of money from their secret donors” and had “the media behind them trashing us and spinning their narrative”.

The attacks on journalists were later criticised by the SNP’s political rivals, who suggested it was a sign of the state of the party which had been trailing Labour in the polls north of the Border.

Responding to the comments made by the NUJ leaders, Russell Findlay, the Scottish Conservative's justice spokesman, and a former newspaper reporter, said last night: “Journalists perform a hugely important role in our democracy by informing the public about elections and should not have to put up with idiotic abuse and cowardly threats.

“There should be zero tolerance for such behaviour, whether it happens in person or via social media.”

Scottish Liberal Democrat Willie Rennie MSP said:  “This is a fairly telling warning from the NUJ. The SNP have a questionable reputation when it comes to ensuring all members of the media feel comfortable at their press conferences.  

“The purpose of these events is to allow every party to set out their stall and for journalists to scrutinise their proposals freely. 

“No political party is above that principle, and I hope the SNP keep that in mind tomorrow.”

The SNP and Labour were approached for comment.