Michael Matheson is set to face a record ban from Holyrood over an £11,000 bill racked up on his parliamentary iPad.
MSPs will decide on Wednesday if they agree with the Standards Committee recommendation that the former health secretary should be barred from Holyrood for 27 sitting days and lose his salary for 54.
The Falkirk West MSP, who quit the cabinet in February, was found to have breached the code of conduct for MSPs by racking up the huge roaming bill while on holiday in Morocco, which later he said was caused by his children watching football.
Initially, Matheson had attempted to use a combination of his office costs and expenses to cover the bill, but he later said he would pay it himself after the issue was made public.
Labour, Conservative, Lib Dem and Scottish Green MSPs are expected to back the motion calling for sanctions to be imposed on Matheson.
First Minister John Swinney previously said he would not support sanctions, but an SNP motion at Parliament now backs it.
Speaking ahead of the Holyrood debate, Scottish Tory leader Douglas Ross said: “Public trust in MSPs is on the line in today’s vote – and it will be destroyed if SNP and Greens MSPs do a dodgy deal to save Michael Matheson’s skin.
“Michael Matheson outrageously billed the taxpayer £11,000 for roaming charges he racked up while on holiday. He then repeatedly misled the public and Parliament to cover his tracks and only paid back the money when he was rumbled.
“Michael Matheson would have been sacked in any other walk of life for what he did. That is why opinion polls show the vast majority believe he has to go.”
The Scottish Tories will force a separate vote on Matheson’s future on Wednesday, calling for him to resign.
But it is unlikely that motion will pass, with the Scottish Greens not expected to support it and party MSP Ross Greer describing it as “cynical”.
The Greens will lodge an amendment to the Tory motion seeking to delete calls from the Tories for Matheson to step down, dismissing them as “naked politicking” and “wholly malicious.”
A spokesperson for the Scottish Greens said: “It remains correct that Mr Matheson is held accountable for his actions, and our MSP group will vote for the sanctions excluding him from parliament and sacrificing his salary.
“This has been a truly unedifying process in which Tory MSPs have been exposed for their naked politicking and have tabled a motion that has been wholly malicious in nature. Nobody will take seriously the idea that Douglas Ross can present himself as a champion of truth and honesty in politics.
“However, any attempt by the SNP to try and water down the proposed sanctions would be unacceptable to us. A line should now be drawn under the matter.”
Scottish Labour leader Anas Sarwar accused the SNP of “putting their party interests before the good of the country”.
“John Swinney and the SNP are using the Boris Johnson and Conservative Party playbook – putting personal relationships before the integrity of Parliament,” he added.
“John Swinney is trying to defend the indefensible by backing Matheson who was found to have attempted to misuse £11,000 of public money.
“It’s completely and utterly unacceptable.”
His party, Sarwar added, was “dedicated to cleaning up politics”, including by introducing a Bill that would include a recall process to sack suspended MSPs.
Following the announcement of the sanctions, Swinney described the findings of the Standards, Procedures and Public Appointments Committee as “prejudiced”.
He said Tory MSP Annie Wells had tainted the process through comments she made last year, describing Matheson’s explanation as being “riddled with lies”.
Speaking to journalists on Monday as he campaigned in Dumfries ahead of the General Election, Swinney said he had “deep concerns” about the process.
“I just feel I have got to point out something I think is wrong with the Parliamentary process,” he said.
“I don’t think it would say very much about me if I just turned a blind eye to something that in any other walk of life people would be raising deep concerns about.
“In any other field, if somebody prejudiced a process there would be enormous concern being raised and I don’t think it would say very much about me if I ignored that.”
Swinney refused to say if SNP MSPs would be whipped to vote against the sanctions against Matheson when they gather at Holyrood on Wednesday.
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