By a Newsnet reporter
The parliamentary private secretary (PPS) to Scottish Labour leader Johann Lamont has stepped down from her position after less than a year in the role.
Siobhan McMahon was elected for the first time in 2011 as a list MSP and was asked by Lamont herself to take up the PPS position.
In November last year the Sunday Herald, reported that colleagues had not warmed to her uncompromising style which was described by party sources as "far too aggressive and abrupt."
The newspaper has since accepted the Labour MSPs insistence that she was not removed but took the decision to withdraw after discussions with Johann Lamont.
Writing in her blog, Ms McMahon said: "My decision to withdraw from the post was taken in conjunction with Johann, without rancour, and with her full understanding and support. We both felt that the role was too time consuming, and required me to spend a disproportionate amount of time away from my constituency duties (attention to which is my foremost priority)."
The 27 year old, who previously worked for her Labour MSP father Michael as a paid researcher and had also worked for Labour MP Jim Murphy, has faced claims of an abrupt manner before.
In September Ms McMahon faced claims that she had verbally intimidated a sex industry worker who had visited the Scottish Parliament in order to discuss prostitution with a group of Labour MSPs, including Ms McMahon.
According to the worker, the Labour MSP addressed her in such an aggressive tone it reduced her to tears.
Writing on her blog, the individual said: "I can’t recall exactly what she yelled, because I was so shocked at being shouted at I kind of neglected to pay attention to the details, but it concluded with the observation that ‘the way that democracy works’ is that we can have differing opinions.
The person added: "So then I cried, through a mixture of shock, fury, and, well, sadness I guess. I kind of hoped the debate would be slightly more elevated. Silly me."
The Labour MSP, who is a member of Parliament’s Equal Opportunities Committee, was also taken to task in August after appearing to suggest that women should not be allowed to have abortions even if they are raped.
Ms McMahon claimed US President Barack Obama should “hang his head in shame” after he tweeted that everyone should know his opponent Paul Ryan was against all abortions for women, even those who had suffered incest or had been raped.
Claims that his daughter had been removed from her PPS role to Johann Lamont due to her uncompromising manner were denied by her father Michael McMahon, who tweeted: "I see pantomime season has started early. Oh no she didn't!"