It was sent by the head of the Nationalists’ student wing and executive committee member Gail Lythgoe in an effort to persuade leaders of an influential women’s network to attend a protest against Ian Davidson. Mr Davidson said he was “shocked” by the development and is now consulting lawyers. First Minister Alex Salmond is facing calls to hold an inquiry into “dirty tricks” tactics in the SNP, after outgoing Labour leader Iain Gray used his farewell speech to conference delegates to warn against “ugly” smears. The e-mail is the latest twist in a high-profile spat that saw Mr Davidson, the chairman of the Scottish affairs select committee at Westminster, accused of threatening Nationalist committee member Eilidh Whiteford with a “doing” during a private meeting. Mr Davidson denied using threatening language and was backed by other members of the committee, but Dr Whiteford is now boycotting future committee meetings until he quits. A meeting of the committee was held yesterday afternoon and it emerged Ms Lythgoe, who works as a researcher for Nationalist MSP Joan McAlpine, had circulated an e-mail to the Scottish Women’s Budget Group, a body that promotes gender equality. In her e-mail, Ms Lythgoe stated: “He [Mr Davidson] has a history of bullying and intimidation particularly towards females, but not limited to them.” Calling on group members to join the protest at Glasgow City Chambers, she adds: “This showing of solidarity must be non-partisan and we need your help to do this – only then will be [sic] message be credible and strong enough.” The protest did not go ahead, but the communication prompted a furious reaction from Mr Davidson. He said: “I’m shocked to hear of this development. I have this evening been in touch with my lawyers to seek advice.” A Scottish Labour Party spokesperson added: “This leaked e-mail is a smoking gun and utterly reprehensible. It contains the most vile, false smear and shows the extent to which the dirty tricks campaign against Ian Davidson is orchestrated by the highest levels of the SNP. “Gail Lythgoe is not just an SNP activist – she is the head of the SNP’s official student wing, sits on the party’s National Executive Committee, and is paid by the taxpayer to work as an MSP researcher for one of Alex Salmond’s closest allies. “We know the SNP want to get rid of Ian Davidson because his committee is asking the difficult questions on the referendum, but an orchestrated smear campaign being prosecuted by SNP insiders is beyond comprehension. “It is flabbergasting she openly asks respected campaigning organisations in Scotland for their help, saying only then would the SNP’s dirty tricks campaign ‘be credible and strong enough’.” An SNP spokeswoman said in a statement last night it was “not an issue of party politics”. She added: “We hope people of all parties and across civic society will take the opportunity to respond positively to the concerns raised by Dr Whiteford, Green MP Caroline Lucas, Women’s Aid and the Scottish Women’s Budget group, in particular, to the budget group’s call for Scotland’s political future to be marked by a commitment to equality.” Angela O’Hagan of the Scottish Women’s Budget Group last night insisted that the organisation had not been used by the SNP. She said: “The Scottish Women’s Budget Group is completely unaligned. We are a non-party political. I’ve no doubt that our members belong to a whole range of other organisations, some of which will be political parties, but that’s across the political spectrum.” The body issued a letter to the media last week, with a host of signatories, hitting out at the language used by Mr Davidson. He has insisted that he only used the phrase after Dr Whiteford had faced criticism from other committee members and it was said in the context of “you’ve had a doing, now let’s move on”. The latest controversy is the second “dirty tricks” row to engulf the SNP in the past week. First Minister Alex Salmond was forced to apologise to MSPs for misleading parliament on Thursday after reading out a false quote from an electoral expert which claimed to back the SNP’s independence referendum. It followed a newspaper article earlier that day in which Professor Matt Qvortrup had suggested the two-question plan was not feasible. Mr Salmond told MSPs that a letter from the academic made it clear that he found the SNP’s plans “fair and reasonable”. In fact, these words had been written by SNP spin doctor Kevin Pringle, prompting an apology from the First Minister. Labour now wants the SNP leader to order an investigation into the latest row. “Alex Salmond must apologise for these dirty tricks today and order an independent inquiry into the ethics, practices and management of the SNP student wing,” a spokesman added. “Either the party has lost control of its activists and researchers, or their smears are being condoned at the highest level.” On Saturday, Mr Gray warned the three contenders vying to replace him as Labour leader that they would face a barrage of “ugly” attacks by SNP supporters. “You will be attacked, you will be smeared, you will be lied about, you will be threatened,” he told a special conference. “The ‘cyber Nats’ and the bedsit bloggers will call you traitor, quisling, lapdog, liar and worse. “They will question your appearance, your integrity and your sexuality. They will drag your family and your faith into the lies and the vitriol. If you are a woman it will be worse.”