The premise of a coalition government comprising the Scottish National Party and the Scottish Greens is not new. It has been raised in previous Holyrood election campaigns, including the 2016 contest, without ever materialising in practice. However, in present political circumstances, the concept seems more plausible than before. A combination of the joint desire for an independence referendum and independence in the next term with the electoral and parliamentary calculus at hand could reasonably lead to the first SNP-Green coalition in Holyrood’s history.

In multiple respects, the Scottish Parliament resembles other European legislatures more than it does the UK Parliament – and intentionally so: a (mixed) proportional representation electoral system, a hemicycle chamber and multiparty cooperation on budgets and wider legislation, among others. Yet, one common European feature has been missing at Holyrood for some time: coalition government. The last one ended back in 2007, when the SNP minority government replaced the Scottish Labour-Scottish Liberal Democrat coalition government. Illustratively, those 16-year-olds just eligible to vote in this Holyrood election were two years old at the time.

While every democratic contest is consequential, this Holyrood election gives the impression of being a defining moment of decision. The future directions for an independence referendum, the management of the coronavirus pandemic, and social and economic recovery will all be shaped by its outcome. Holyrood seat projections based on opinion polls have varied sufficiently throughout the election campaign to make it indeterminate whether the SNP will secure a parliamentary majority. This context will frame considerations of a possible coalition by the parties, as it would also frame the rationale that they would present to party members and voters, if one were formed. Should a coalition prove amenable to the SNP and Scottish Greens, its formation and operation would require new forms of cooperation and compromise between them.

Political calculations for the two parties

In deciding whether to pursue a post-election coalition, the leaderships of the two parties will assess the advantages and disadvantages for their side. For the Scottish Greens, such a coalition would foremost be an opportunity to enter national government for the first time in their history. Parties and politicians generally aspire to be in government to implement their vision and policies – and that desire can sometimes be justification enough to enter a coalition. As the junior party in the coalition, however, the Greens would by definition face greater structural limitations than the SNP: (far) fewer ministers, fewer Greens-attributed policies and fewer MSPs. Nevertheless, their degree of practical power in the coalition would not be predefined. It would instead be determined in large measure by how skilfully the Greens could parlay their position into effective influence.

In Europe and elsewhere, junior coalition partners do not always fare well in subsequent elections. They can lose support if enough voters believe that they have compromised their principles too much or enabled the senior coalition partner to implement its agenda. Yet, the Scottish Greens could well avoid such an eventuality this time. As we know, Scottish politics is significantly artificially distorted by the independence debate. Many of the normal expectations of parliamentary democracy do not apply. For instance, if an SNP-Green coalition ultimately facilitated a new independence referendum, the Greens may in fact gain support, rather than lose it, from pro-independence voters for enabling the SNP’s agenda (which it shares in that respect).

In fact, the prospect of independence could serve as another strong motivation for the Scottish Greens to enter government. If a referendum took place within the next parliamentary term (as both parties propose), and the people voted for independence, the Greens would be part of that pivotal government which would implement the initial stages of the path to statehood. For all the current suggestions that the ensuing Scotland-UK negotiations could be conducted in some Scottish cross-party or no-party fashion, the reality is that the Scottish Government would drive the Scotland side of the independence process. In government, then, the Scottish Greens would have an integral role in making independence happen, which would surely appeal to the party.

For the SNP, a coalition will presumably be viewed predominantly through the lens of an independence referendum. The party faces an imperative to deliver a referendum within the next parliamentary term, as it has promised in this campaign. Many party members and those in the wider independence movement will likely hold the party to that promise. If a referendum does not happen next term, it is highly questionable whether the SNP could go into the 2026 Holyrood election promising its recurring ‘Scotland’s future in Scotland’s hands’ message and expect the enthusiasm, support or success to which it has become accustomed. Should a coalition with the Greens secure a referendum which was accepted by the UK Government and could lead to effective independence, then other considerations could well become secondary to the party.

In most circumstances, a senior party would form a coalition with one or more junior parties to provide the government with a parliamentary majority for the purposes of general governing. Yet, given the SNP’s predicament, its motivation for a coalition would likely be more about an independence referendum than governing. If the SNP wins a plurality, then a coalition with the Scottish Greens would ensure a parliamentary majority for the government and constitute the proposed mandate for a referendum. If the SNP wins a majority, then a coalition with the Greens would produce an enhanced majority for the government and make the referendum mandate appear even stronger. While the outgoing parliament already had a pro-referendum majority, the government majority is the chosen vehicle to break the Scotland-UK impasse on a referendum.

Outwith the matter of a referendum, it is less evident whether a coalition would appeal to the SNP. The party chose to operate as a minority government in 2007 and 2016. In 2016 in particular, an SNP-Green coalition would have delivered a government majority, which could have resulted in different dynamics in respect of opposition to Brexit and changes to devolution and of an independence referendum. Since the SNP is used to running a minority government and making ad hoc parliamentary compromises with the Greens or others, the appeal of a two-party majority government and bringing those negotiations inside the government may be more limited. Beyond the explicit calculations, an SNP-Green coalition could make the Scottish Government appear different and refreshed, which may suit the SNP. It could look new without the SNP leaving office.

Forming a coalition government

In the aftermath of the election, should the SNP and Scottish Greens leaderships decide to explore the formation of a coalition government, general practice would consist of a series of steps. Party leaders would appoint negotiators to explore the viability of a coalition and, if so, to negotiate a coalition agreement. Ministerial portfolios, policy positions and internal governance mechanisms would all be subjects of discussion. If negotiations were successful, the coalition agreement would have to be approved by each party according to its own procedures, potentially involving votes on the agreement by the parliamentary group or the party membership. Provided that the coalition agreement was endorsed by both parties, the new government would be formed and take office.

Ministerial numbers and roles are normally the most salient matters. In Scotland’s last coalition government, the Scottish Liberal Democrats had approximately 25% of the parliamentary seats in the two-party coalition and a relatively equivalent percentage of senior ministers (3 of 11 – excluding the Lord Advocate) and junior ministers (2 of 7 – excluding the Solicitor General). Their party leader was also Deputy First Minister. Based on current projections, a reasonable hypothetical scenario could deliver the SNP 64 seats and the Scottish Greens 11 seats. Here, the Greens would constitute approximately 15% of the coalition. Provided that the size of government remained unchanged, a rounded proportional basis would give the Greens 2 cabinet secretaries out of 12 (including the First Minister) and 2 ministers out of 14 (excluding the law officers).

The Scottish Greens could also take the title of Deputy First Minister. Their co-leader system could make assigning that role more complex, if both co-leaders were elected to the Parliament. It has been speculated that the Greens could provide the Parliament’s next Presiding Officer, which would presumably affect ministerial allocations. A reasonable proposition might see the Greens then take 1 cabinet secretary and 2 ministers, along with a Green becoming Presiding Officer. Using existing portfolios (which could of course change), we could imagine a theoretical Greens ministerial team consisting of: the Deputy First Minister and Cabinet Secretary for Environment, Climate Change and Land Reform; the Minister for Europe and International Development; and the Minister for Older People and Equalities. The SNP would logically take all other ministerial roles. Actual decisions would depend on the exact electoral arithmetic, the Greens compromise threshold to secure a deal and the SNP strength of desire for a coalition.

Coalition negotiations would also cover the joint policy platform for the prospective government. Incorporating greater policy detail reduces the substantive basis for subsequent intra-coalition policy disputes (even if such disputes still arise). Given the circumstances, the SNP and Greens could conceivably seek agreement on an independence referendum (and potentially wider aspects of independence) as the first priority, and then all other policy areas as the second priority. As evidenced in their respective manifestos, the SNP and Greens offer distinct proposals in a number of domains, and the two parties would have to decide which compromises they would make to secure an overall deal. A coalition agreement would normally be expected to cover the full parliamentary term. However, if a referendum took place and returned an independence majority, most policy plans in the agreement would be overtaken by the resulting independence process.

An effective coalition government requires sufficient joint decision-making structures. It would be normal for a small, high-level group consisting of party leaders and potentially their deputies to be formed. This group would set the coalition agenda and resolve significant coalition disputes. The cabinet would be expected to take on greater importance in the business of government, as a deliberative forum for the parties and individual members (though that function would be fairly modest, if the Greens had only one cabinet member). Formal cooperation would be developed between party whips and business managers. The SNP and Greens are acquainted with working together informally in the Parliament. As a coalition, their cooperation would be formalised and become part of the operation of government. The objectives would be to ensure the smooth functioning of the coalition and to manage and resolve differences before they manifested openly.

Impact of an SNP-Green government

As the first pro-independence coalition, an SNP-Green government would change the dynamics in Holyrood. With its majority, the budget and other legislation (including on an independence referendum) would easily pass, provided that the coalition remained united. Intra-coalition talks would replace the need for inter-party negotiations, though hopefully the government would continue to seek common ground with opposition parties, in the spirit of cross-party cooperation. Unless the Alba Party entered the Parliament (or some unforeseen eventuality), the opposition would consist entirely of pro-UK parties. If the Greens perform as opinion polls suggest, they could also take on a larger role in the Parliament, securing a committee convenership.

The durability of the coalition would depend on the extent to which the partners could maintain consensus and commonality. Successes or failures in information sharing, compromise and weathering the inevitable difficulties would all be factors in the health of the coalition. The parties would each assess how they were faring, including whether they were accomplishing their policy priorities and whether they were maintaining their distinct identities and relevance with voters. Such considerations would be more acute for the Scottish Greens, as the junior partner in its first government. Internal party cohesion would be an important indicator. Despite securing the initial support of party members to enter the current Irish tripartite coalition, the Irish Green Party is now publicly and notably divided on its role in government and the party’s future direction.

The legacy of a successful SNP-Green government could be significant for Scottish politics. If the coalition worked satisfactorily for both parties, it could become a template for future cooperation. The SNP could govern as the senior party without the preoccupation of securing a parliamentary majority on its own. The Scottish Greens could ensure their continued place in government. Both parties could benefit from renewing their coalition, especially if they were able to maintain a combined majority of seats – as long as they garnered sufficient policy achievements and retained the support of their respective voter bases. The SNP and Greens each want this Holyrood election to be Scotland’s last under devolution. Establishing a Scottish state would be a transformational process that would bring wide-ranging change. In that environment, a stable and effective SNP-Green coalition could prove appealing to a Scottish electorate which had voted for independence. Under that scenario, their partnership could define the first era of the new Parliament of Scotland.