Nicola Sturgeon facing questions over Derek Mackay's departure as finance secretary

Scottish Labour leader Richard Leanord says Nicola Sturgeon should have sacked Derek Mackay as finance secretary, instead of allowing him to quit after the scandal resulting from his hundreds of messages to a teenage schoolboy.

He has written to the First Minister demanding to know why she opted to let Mr Mackay resign from her cabinet, rather than immediately dismissing him.

He is also demanding that the SNP leader make any phone records and notes of any conversation she had with Mr Mackay public after learning about his behaviour.

In his letter to the First Minister Mr Leonard said: "The conduct that the Cabinet Secretary has admitted to would, in my view, merit a dismissal from office by the First Minister rather than allowing a resignation."

The Scottish Labour leader has already condemned Mr Mackay's "predatory" behaviour after it was reported he had sent 270 messages to a 16-year-old who he had befriended on Facebook and Instagram.

The 42-year-old politician, who came out as gay in 2013, is reported to have told the youngster he was "cute" and offered to take him to a rugby game and out to dinner.

Mr Leonard said it was "deeply concerning that such a senior member of this parliament was not immediately dismissed" by the First Minister.

The Labour leader said: "The fact that his behaviour was directed towards a teenage schoolboy should have been enough for the First Minister to take decisive and fast action."

He insisted: "It is now vital that the full circumstances leading to Derek Mackay's resignation are revealed publicly.

"The contact Nicola Sturgeon had with Mr Mackay after she was made aware of the allegations should be shared immediately."

Meanwhile Liberal Democrat MSP Alex Cole-Hamilton wants the law to be changed so that all MSPs are required to go through the same background checks that someone working with children or vulnerable groups would have.

He plans to bring forward amendments to the Disclosure Bill when it is formally lodged, that would require elected politicians to be vetted by the Protecting Vulnerable Groups (PVG) scheme.

Mr Cole-Hamilton insisted the change was not being proposed in response to any single incident - adding that he had been "exploring this proposal for months".

But he stated: "I have always been conscious that with elected office comes a huge power imbalance. We know that people can use their status to manipulate, target and exploit. People need protecting from that and this needs to be done through law."

The Liberal Democrat added: "Parties each have their own candidate approval processes, but none will offer the same level of protection as a PVG certificate.

"The prospect and knowledge of this extra independent check will also serve the purpose of deterring people who would be inappropriate from standing for public office in the first place."

He said MSPs could "often" have unsupervised contact with children or vulnerable adults, as he stressed: "Parents should know their children are in the presence of someone who can be trusted and has been checked up on.

"But those assurances simply don't exist at the moment, and that's wrong."

Mr Mackay stepped down hours before he had been due to announce Holyrood's budget for the coming year to MSPs, with public finance minister Kate Forbes standing in for him at the last minute.

In his resignation statement he accepted he had "behaved foolishly" and apologised unreservedly to the teenage boy involved and his family.

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