The Scottish Greens today set out their ‘red lines’ for any coalition. These lines are policies that the party won’t cross to enter government. it’s almost certain the next Scottish Government will be led by either the SNP or Labour. These red lines mean that a coalition including the Greens will be radically different to one without the Greens.

The red lines confirm the Scottish Greens’ position as the only party opposing the cuts agenda. This distinctive approach means the Greens are well placed to voice the widespread opposition to the cuts in government as well as in Parliament.

The Scottish Greens have learnt from the mistakes of both the Irish Greens and the Liberal Democrats in the UK. Both the Irish Greens and the Liberal Democrats sold themselves far too cheaply. For the Liberal Democrats its seems that a referendum on the Alternative Vote was enough to buy their support the destruction of public services and £9,000 a year fees for students – despite pre-election pledges to the contrary. The Irish Greens chose to support a cut-throat deficit reduction package featuring a wide range of cuts in return for a grow-your-own vegetables scheme and cycle to work programme.

But the Scottish Greens have set down three promises to their electorate that mean any lead partner will have to radically alter their programme for government. The key to this is the third red-line: “Green MSPs would not play any role in an administration which makes cuts to Scottish services that worsen inequality.” This will determine the direction of either an SNP, or a Labour-led government. Neither the SNP nor Labour is enthusiastic about cuts in the way the Conservatives or Liberal Democrats are. But both are centrist parties intending to make cuts which will worsen inequality.

By laying down an absolute refusal to participate in any government making these cuts, the Greens are demanding that a much larger party bend to their will. This is almost certainly the only way for a small party to succeed in a coalition. Where the Irish Greens have been drummed out of the Irish Parliament, and the Liberal Democrats look like having a very difficult election in Scotland and Wales, the Scottish Greens will be able to take the credit for Scotland avoiding cuts.

It is somewhere between difficult and impossible to see the SNP and Labour going into a ‘Grand Coalition’. This leaves the Greens as the only coalition partner for either SNP or Labour that is not part of the toxic coalition at Westminster. It will be hard for Labour or SNP to have either the Conservatives or Liberal Democrats as junior coalition partners. In full knowledge of this the Greens are playing very hard to get.

The other two red lines are vital pledges that will deliver a better Scotland. The first is that there will be no new nuclear or coal-fired power stations built in Scotland, or extension of the life of existing nuclear plants. It will be very difficult for Labour, whose leader Iain Gray has a nuclear power plant in his constituency, to commit to the imminent end of nuclear power in Scotland. The SNP agree on this policy, but have been enthusiastic supporters of a new coal-fired power station at Hunterston.

The second pledge is that “Green MSPs will under no circumstances assist any government in the reintroduction of tuition fees or a new graduate tax. Greens opposed the Labour-Liberal Democrat ‘graduate endowment’, introduced in 2001, and Green MSPs voted with other parties to abolish it in 2008.” This is a position shared by Labour and the SNP. The Liberal Democrats have tried to use this issue as a way to distance themselves from the Westminster coalition.

On the face of it the commitment on fees is the easiest for other parties to agree. This, however, may be more complex than it seems. The Greens have set a strong line on other cuts to expenditure. It will be difficult to find things to cut to pay for continued student support that don’t increase inequality.

The absolute commitment to these pledges will have to sweeten other difficult decisions for Greens. It will be difficult for Greens to see over £2bn wasted on an unneeded third Forth Road Bridge, or over £200m wasted on an Aberdeen bypass. Working with Labour will mean difficult decisions on pointless compulsory sentences for carrying a knife, and a return to counter-productive punitive short-sentences for minor offences. So it is vital for the Greens that they get all three of their red lines into a coalition agreement.

The Scottish Greens bossing a coalition in which they are the junior partner will be as much a landmark for the Green movement as the election of Caroline Lucas, or the first Green provincial government in Germany. The ambition is unmistakeable and the issues are well chosen.