SNP MP Michelle Thomson is not being investigated by the Parliamentary Standards Commissioner, according one of those who asked for a probe.

Former Liberal Democrat MP John Barrett is reported to have asked the commissioner to investigate Thomson’s property deals in the wake of a police probe into her solicitor, but told the Edinburgh Evening News the commissioner had already rejected that request as the deals took place before she was an MP.

Police are investigating lawyer Christopher Hales, who was struck off over a series of property deals done on Thomson’s behalf.

The commissioner wrote to Barrett: “The allegations relate to purchases made in 2009/10. Ms Thomson first became subject to the House of Commons Code of Conduct in May 2015, when she became a Member of Parliament. I do not, therefore, think that the Commissioner could investigate this matter.”

Earlier this week Tory backbencher Andrew Bridgen said he had referred Thomson to the commissioner, but The National understands he has not yet contacted the commissioner’s office. If he does, an investigation may still follow.

There was another development in the case of Hales yesterday when the Law Society of Scotland said it passed on a suspicious activity report to the Serious Organised Crime Agency (now the National Crime Agency) in October 2011.

The National Crime Agency could neither confirm nor deny the report.

Questions have been asked about why it took so long for the Law Society to report Hales to the Crown Office after it struck him off in May 2014.

On 13 occasions, the solicitor failed to inform mortgage providers about “back-to-back transactions, cash-backs, increases in prices and deposits being provided by a third party”. These actions, the society said, could facilitate mortgage fraud. Despite this, the society did not inform the Crown Office about Hales until July 2015.

Yesterday, the society rejected calls from Nicola Sturgeon and Kezia Dugdale to release documents about Hales’ tribunal.

A society spokeswoman said: “We have sought to be as open as possible about ... this case, the steps taken that led to Mr Hales being struck off as a solicitor and our reporting to the relevant authorities.

“However, it would be irresponsible to release all of the files ... Not only would publication of this kind go against our data protection obligations but it could jeopardise the police investigation and potentially prejudice any legal proceedings.”

She promised police the society's "full assistance.”