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Scottish independence: How to draw a line in the sea

DISPUTED WATERS: Berwick lighthouse, from where an English-Scottish maritime border would begin - Credit: Getty Images/RooM RF

Among the many complex issues that Scottish independence would throw up would be where to draw a line between English and Scottish waters.

Should Scotland vote for independence at some point in the coming years, the issue of where its land border with England should lie will be among the simplest of subjects to resolve. The matter of where that borderline should be drawn in the waters off the Scottish and English coasts will likely be far more complex and controversial, however.

For while a sea boundary between the two already exists, and is tacitly accepted by Holyrood, in the event of Scotland becoming independent, its new government would certainly ask fresh questions over whether it is in the right place, and specifically, who would own the older North Sea oil reserves, some of which currently lie on the ‘English’ side.

That current boundary – under the terms of the UN Convention on the Law of the Sea and formalised under the Scottish Adjacent Waters Boundary Order of 1999 – is drawn on the basis of equidistance between the nearest land points in each country.

So, it heads away from the border, north of Berwick-upon-Tweed, in a north-easterly direction, at right angles to the coast. However, the rule of equidistance pulls it increasingly southward as it goes out to sea until, by the time the time it ‘strikes oil’, it is running almost due east, leaving oilfields such as Clyde, Argyll and Fife in ‘English waters’.

That detail is, at present, academic, as it is the UK government that administers Crown property, including petroleum. However, the Scottish government chose a potentially ambiguous wording in its 2014 report, ‘The Land of Scotland and the Common Good’: “While all Crown property rights in Scotland belong to Scotland as a sovereign territory, the Crown’s ownership of ‘petroleum’ in Scotland is administered by the UK government.”

Separate to that boundary is another that divides the North Sea into two separate legal areas to the north and south of the 55th parallel (near Berwick), meaning that, if you murder someone on an oil platform you will expect to be tried under Scottish law, whereas if you commit the crime on a gas platform, off East Anglia, you’ll face English justice.

“This was the line prior to devolution,” says professor Philip Steinberg, professor of political geography at Durham University and head of its International Boundaries Research Unit. “Prior to devolution it didn’t matter in terms of revenue but it was easy for the respective police and court systems. From an international law standpoint, that’s not a line that resembles anything – it came about long before anyone was thinking about setting precedents.”

However, “setting precedents” is precisely how some nationalists would prefer to see the present “boundary of convenience”.

“If you think Brexit is complicated, you ain’t seen nothing yet!” says Uisdean Vass, a Gaelic-speaking nationalist and legal consultant, commenting on how the dismantling of the UK might play out. “You have to assume that everything would be open to debate. We haven’t since 1707 set out to negotiate matters as an independent country.”

A lawyer for 35 years, advising oil service companies and regulatory agencies around the world, Vass and colleagues modelled how a Yes vote in the 2014 referendum might impact on the ownership of reserves.

“The issue is becoming hot again,” he says now. “I was just about to destroy all the papers a few months ago and now I sense these issues becoming important again.”

The starting point for the North Sea would be as defined by the Law of the Sea, or the existing south-west to north-east line drawn at devolution “although you could justify lines to the north and south of this under ‘equidistance’”, suggests Vass.

But, he continues: “There’s another line that nationalists are very keen on, which is a straight line from Berwick as defined by the Civil Jurisdiction Order of 1987.”

For Steinberg, however, recognition of the boundary acknowledged at the time of devolution, while it would not give Scotland control over all the oil, would reinforce its credentials as “an independent nation” ready to follow international law. But he concedes: “Almost anything could be agreed under post-referendum negotiations.”

The important thing would be that those conducting the negotiation had a thorough understanding of the Law of the Sea.

While once the high seas accounted for all ocean beyond the range of a cannonball, the world’s oceans have progressively fallen under the jurisdiction of states. Such has been this advance, that more than 30% of our oceans are now within this category. But the need to resolve overlapping claims means that approaching 500 international maritime boundaries have needed to be drawn.

To date, barely half these boundaries have been even partially agreed and it is into this vacuum that Steinberg and his colleagues at IBRU, have stepped. Originally known as the International Boundaries Research Unit, IBRU has developed valuable expertise that can help improve understanding of likely outcomes when maritime boundary disputes require resolution.

“It’s a unique thing that we do and I think it’s incredibly important because there is no guarantee that conflicts will be easily resolved but, by creating a common standard, we enable parties that want to settle amicably to do so. If the sides don’t know the rules that’s not going to happen.”

Where ocean boundaries become more complex is on the ‘extended continental shelf’, beyond 200-nautical mile exclusive fisheries zones. Here, explains Steinberg, the Law of the Seas permits states to claim mineral rights in more distant waters.

In broad terms, this can be as far as 350 nautical miles, or 100 nautical miles beyond the point at which the sea depth reaches 2,500 metres – although there are other considerations that come into play, such as ‘contiguity’ and the length of the line being drawn.

“So, with geological and bathometric additions, a state can extend exclusive rights ever further,” says Steinberg.

A case in point, and one that has been in the public eye recently is the Arctic Ocean. Here, the Lomonosov Ridge, a subsea spur of the Asian continental shelf, runs 1,100 nautical miles from Russia most of the way to Greenland.

“Canada, Greenland [Denmark] and Russia can say it’s an extension of their continental shelf,” says Steinberg. “In this case all three countries have filed claims with the UN and none of them has been assessed yet. Canada and Russia have filed claims that overlap each other near the North Pole.” Denmark’s claim audaciously overlaps both, but Steinberg believes the hostile Arctic environment makes such argument largely academic – for now at least.

Perhaps of more pressing concern is the ongoing simmering tussle between Greece and Turkey in the Aegean, where there both countries claim areas where oil and gas has been found. The former views the sea as a kind of Greek lake, peppered with Greek islands.

Precedent, however, is not entirely on Greece’s side, and that precedent is an old one and one that lies very close to the UK. “Following normal principles of international law, the boundary between the UK and France would fall between Jersey and France,” says Steinberg. “But there was a negotiated agreement in the 1960s, before the Law of the Seas, to draw a line down the middle of the English Channel, excluding the Channel Islands, but the islands would get their own 12-mile exclusive zones (or up to the median line with the French coast, if closer).

IBRU has no magic wand to sort out conflicting Aegean claims, where things are further complicated by the unresolved dispute over the divided island of Cyprus, not to mention Israel and Palestine. At the same time, Turkey appears emboldened since EU accession talks stalled in 2018.

“It’s difficult to achieve a political solution in a situation in which countries don’t like each other, or even recognise each other,” concludes Steinberg bluntly. There lies a lesson for England and Scotland, should such a separation occur.

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