Mr Justice Treacey's ruling on the gay blood ban has the potential to impact on issues like fracking, planning and education.
You have to bore down past the headline finding that Edwin Poots' decision to maintain a lifetime ban on gay men donating blood was "irrational".
The deeper implications lie in the judge's finding that Mr Poots had also exceeded his authority as health minister.
The court ruled that "the lifetime ban is both controversial, in that it has generated much publicity and public debate, with highly polarised views, and cross-cutting, in that it touches on equality issues and, as such, the minister has no authority to act without bringing the matter to the attention of the Executive Committee".
In other words, ministers shouldn't take a solo run on such issues; they should seek collective agreement.
That undermines the so-called 'silo system', whereby ministers largely did their own thing provided they kept within budgetary limits and signed up to a general Programme of Government objectives.
Generally, Sinn Fein and the SDLP champion ministerial independence.
They fear that collective decision-making will end up producing majority rule.
In a compulsory coalition, independence gives nationalists and smaller parties more room to pursue their own policies in their departments.
The DUP, as the largest party, tends to favour joint decisions, but now changes it wrote into the silo system in the St Andrews agreement have come back to bite its minister, Mr Poots (below).
The judge quoted the ministerial code, which states that any matter which "cuts across the responsibilities of two or more ministers", or is significant, or controversial, should be brought to the Executive.
That is set out in paragraph 24 of the code, which is available online, but it had remained a dead letter until now. Mr Poots has said he thought that it was up to other parties to call the matter in, not for him to submit it, but that is not the case. The code puts the duty on the minister.
There has been some alarm. "There has been a general Executive view that, if we were to carry it to the level to which Mr Justice Treacey carried it... there would be no spending, or individual decisions, by ministers and everything would have to come to the Executive Committee," Peter Robinson said in the Assembly.
"Obviously, we have to work out where the bottom line is with regard to what it is important for the Executive to deal with."
So there is going to be change as a result of the judgment; it is just a question of how much. There is already a proposal from Arlene Foster to bring the issue of fracking licences, which have the capacity to both impact on the environment and reduce energy prices, to be referred to the Executive. This is another instance in which a local minister – in this case, Mark H Durkan of the SDLP – wants to take the decision himself.
Like Mr Poots on the blood ban, he proposes breaking with overall UK policy on the issue, which is to promote fracking as part of the energy mix.
The John Lewis application to build a distribution hub for the whole island of Ireland and a shopping development at Sprucefield is another major decision which is now likely to be brought to the Executive, instead of being signed off by an individual minister.
So is the future of the Dickson Plan in education. These are big changes to the way Stormont is run and they could nudge us towards a more joined-up form of government.