SCOTTISH Parliament bosses have responded to Tory demands for it to publish a timetable in relation to the Michael Matheson investigation.

In a letter to Presiding Officer Alison Johnstone, Scottish Tory chairman Craig Hoy has demanded to know when the investigation is due to be completed, when findings will be published, if Matheson will be given advanced sight of the report, and if correspondence between Holyrood officials and the Health Secretary will be published.

Health Secretary Matheson admitted earlier this month an £11,000 data roaming bill he racked up while on holiday in Morocco had been caused by his teenage sons using his parliamentary iPad as a hotspot to watch football games.

The cost was initially set to be covered by the public purse, through a mixture of Matheson’s expenses and office costs, but after a row erupted, he announced he would pay the bill in full personally.

The Health Secretary has faced calls to resign or be sacked over the issue after he told journalists there had been no personal use of the device.

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The Scottish Parliamentary Corporate Body (SPCB) confirmed last week it would investigate Matheson and potentially refer him to Parliament’s Standards, Procedures and Public Appointments Committee.

In a letter to Johnstone, Hoy pushed for a timetable to be set out for the probe even though the SPCB said it would complete the work "promptly". 

In response, the SPCB has said it will “proceed quickly” with the probe and Matheson will be invited to contribute evidence in writing.

An SPCB spokesperson said: “The SPCB’s investigation will proceed quickly and with due regard to the need for a fair process and the requirements of the Code of Conduct set by Parliament.

“Due process requires that Mr Mathieson will be invited to contribute evidence in writing following the personal statement he made to Parliament on 16 November.

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“The SPCB has already made clear that in the interest of fairness to all, and to avoid prejudicing the investigation, it will not comment on any further matters that could have a bearing on this process or provide a running commentary.  

“The Corporate Body remains wholly committed to openness and transparency and will release all material it can, when it can, in line with its legal obligations.” 

Hoy wrote in his letter: “The significant amount of interest generated from this scandal means it is imperative for the SPCB to provide details about this investigation so that the public can be confident that a thorough investigation has occurred and that it won’t be a whitewash.”

He also pushed the Presiding Officer on whether there will be a full parliamentary debate on the findings.

He added: “If these outstanding queries are addressed, that would give the public the reassurance they need that this investigation will be comprehensive and will answer why Michael Matheson felt it was appropriate to claim nearly £11,000 from the taxpayer to pay for the bill he incurred whilst on holiday.”