They say a week is a long time in politics.

And the past seven days must have seemed like an eternity for Renfrewshire North and West MSP Derek Mackay.

The SNP man is not the first politician to suffer a fall from grace – but, in Scotland, few have plummeted such a distance in such shocking fashion.

This time last week, the future looked bright for Mr Mackay. He held one of the most important roles in the Scottish Government as Finance Secretary and was being tipped by many as the successor-in-waiting to Nicola Sturgeon and a future First Minister.

READ MORE: Nicola Sturgeon 'banned shamed Derek Mackay from drinking at SNP conferences'

Now his political career lies in tatters, ripped apart by hundreds of text messages sent to a 16-year-old schoolboy.

As he fell on his sword by resigning from his ministerial post, Mr Mackay described his conduct as “foolish.”

For others, his behaviour is seen as much more sinister, with the word ‘grooming’ being used as a suitable description.

When Mr Mackay took his place in Holyrood at around 5.30pm last Wednesday for an hour-long debate on non-domestic rates, a political storm was already brewing behind the scenes.

The Scottish Sun had just made a phone call to Ms Sturgeon’s official spokesperson to ask for comment on 270 messages sent by Mr Mackay to the teenage boy.

At a meeting with Ms Sturgeon a short time later, Mr Mackay tendered his resignation from the Cabinet, although it later became clear he would have been sacked had he not chosen to do so.

On Thursday, the full details of Mr Mackay’s disturbing behaviour came to light.

The Gazette: First Minister Nicola Sturgeon accepted Mr Mackay's resignation as Finance Secretary First Minister Nicola Sturgeon accepted Mr Mackay's resignation as Finance Secretary

According to a redacted transcript, he began sending messages to the schoolboy on August 2 last year.

In the months that followed, more messages were exchanged, even after the politician discovered the boy’s tender age.

Mr Mackay later invited him to the Scottish Parliament and also sent a message at 11.34pm on Christmas Day to ask: “You still up?”

He went on to ask the boy if their chats were “between us.”

When the boy confirmed they were, Mr Mackay added: “Cool, to be honest I think you are really cute.”

It was later revealed he had sent messages while on holiday with his boyfriend, Fraser Bell.

READ MORE: The messages that led to Derek Mackay's downfall

Further allegations followed. A senior SNP staff member claimed Ms Sturgeon banned Mr Mackay from going out drinking during party conferences due to concerns over his behaviour.

Mr Mackay even joked at the 2017 party conference that attendees would not be seeing him at the pub after the event, as “Nicola won’t let me.”

Later, party activist Shaun Cameron, 25, came forward to say Mr Mackay had contacted him on Facebook after they met at an SNP event four years earlier.

Mr Cameron said some of the messages he received from the politician were “quite suggestive,” including one which asked ‘Got any naughty pics?”

As questions over Mr Mackay’s behaviour mounted, he responded by going into hiding.

He deleted his social media accounts and did not appear at any of his planned surgeries last week.

There was no sign of Mr Mackay at his home in Bishopton and, when The Gazette contacted his constituency office yesterday, calls were being diverted to voicemail.

The fallout continues, however.

He has been dropped as honorary president of Renfrew Burgh Band and his position as honorary vice-president of the Paisley and District Battalion of the Boys’ Brigade is also said to be under review.

The Gazette: Renfrewshire Labour leader Eddie Devine has confirmed his party will submit a motion asking for Mr Mackay's resignation as an MSP Renfrewshire Labour leader Eddie Devine has confirmed his party will submit a motion asking for Mr Mackay's resignation as an MSP

Mr Mackay’s constituents now wait with bated breath to hear whether or not he will continue to represent them.

Although he is no longer a minister and is suspended from the SNP pending an investigation by the party, the Scottish Government does not have the power to axe him from his role as an MSP.

READ MORE: Labour leader calls for disgraced Derek Mackay to resign as MSP

Only Mr Mackay himself can make that decision.

He may choose to continue without the support of his party but voters would still expect him to carry out his parliamentary duties.

Some constituents who have been wondering where Mr Mackay has been for the past week may well be willing to accept the idea of him serving as an Independent MSP but are unlikely to put up with one who is ‘invisible.’

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