A SECOND independence referendum could take place this year if Boris Johnson responds positively by the spring to Nicola Sturgeon’s request for a new vote, according to an analyst from a leading think tank.

Jess Sargeant, a researcher on devolution and Brexit at the Institute for Government, who last month correctly forecast that the First Minister would demand that the power to hold an independence referendum be transferred to Holyrood on a permanent basis, has provided a detailed timetable for the process necessary for a new vote.

The National: Nicola Sturgeon

She said that an agreement in principle between the UK and Scottish Government would need to be struck by April with the latter being granted the legal power to hold the referendum by May.

“A second independence referendum could be held this year if the Scottish Government is granted the legal power to do so by May,” she told The National. “But this would require in principle agreement on indyref2 in April at the latest.”

Sargeant set out her calculations using Thursday December 17 as the last possible polling day of 2020 and worked back from that date taking account of the time each political, parliamentary and legal process would take.

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Currently there is a legal requirement for a six week period to designate lead campaigners plus a ten week period to allow voters to engage with the issues, understand the arguments and come to an informed view. Prior to those stages negotiation would take place between the governments and legislation would need to be passed in Holyrood and both Houses of Parliament.

“Assuming the last possible polling day of 2020 would be December 17, the ten-week regulated referendum period would need to start on October 8 at the latest. This would mean the six-week designated period would need to begin by August 27,” she explained.

“The Scottish Parliament will not return from summer recess until August 30 and so the independence referendum bill will need to receive royal assent before the Scottish Parliament breaks up on June 26. As the legislative process would likely take a minimum of eight weeks, legislation would need to be introduced on May 1 at the latest to hold an independence referendum in 2020. So a section 30 order would need to be made before then.”

Sargeant also explained that before a section 30 order could be made it would first need to be approved in draft by both Houses of the UK Parliament and the Scottish Parliament.

She said there is no minimum timescale for this, but it would need to be considered by committees in both Parliaments and be given time for debate. Last time the process took around three months.

She continued: “However, before the section 30 order can be made it would need to be approved in both Houses of Parliament and the Scottish Parliament. There would also likely be a significant period of negotiations between the UK and Scottish Governments about the exact terms and conditions according to which the referendum would be held. So agreement on the principle that a second independence referendum could be held would be needed much sooner than the May deadline.”

She said the process she had outlined would be the minimum timescale and she believed that in practice each of these stages may take longer.

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She said the 2014 independence referendum was held three years after agreement was reached in principle that a vote could take place.

Last year an Institute for Government report argued against a 2020 poll saying major constitutional issues should not be rushed.

Prime Minister Boris Johnson is expected to write this week to the First Minister with his response to her request she sent on December 19 following the SNP’s general election win in Scotland which saw the party get 48 out of the country’s 59 Westminster seats. The SNP had campaigned on a manifesto to hold a new independence vote.

The National: Boris Johnson

The Scottish Tories lost seven of their 13 MP following a central campaign message to oppose a new vote.

Last week Johnson told MPs the 2014 independence vote was a “once in a generation choice” and yesterday Scottish Secretary Alister Jack said a new vote would not be given in the First Minister’s lifetime.

However, Ian Blackford, the SNP’s Westminster leader, said he had had a number of conversations with Conservative cabinet ministers who privately believed it would be a line which would be difficult to hold in the longer term.

He did not name the ministers who he had spoken to.

Last week a Downing Street spokeswoman said the Prime Minister would respond to the First Minister’s letter “in due course”.