Hierachy of rights

It seems according to this snippet today from the Johns case that we do indeed have a hierachy of group rights.

But Lord Justice Munby and Mr Justice Beatson ruled that laws protecting people from discrimination because of their sexual orientation "should take precedence" over the right not to be discriminated against on religious grounds.

So gentles, which group should be at the top of the rights tree, and why? Is my group grievance more important than your group grievance?

And, forgive my ignorance, where in our constitutional law is this stated? And who set it up? And why?

Update
I note this at the end of PA report

The judges also ruled Article 9 of the European Convention on Human Rights only provided a "qualified right" to manifest religious belief.

Looking at Article 9

Article 9 – Freedom of thought, conscience and religion

1. Everyone has the right to freedom of thought, conscience and religion; this right includes freedom to change his religion or belief and freedom, either alone or in community with others and in public or private, and to manifest his religion or belief, in worship, teaching, practice and observance.

2. Freedom to manifest one's religion or beliefs shall be subject only to such limitations as are prescribed by law and are necessary in a democratic society in the interests of public safety, for the protection of public order, health or morals, or for the protection of the rights and freedoms of others.

I guess the judges feel that this couple threaten the 'rights and freedoms of others'

Eunice and Owen Johns, aged 62 and 65, from Oakwood, Derby, went to court after a social worker expressed concerns when they said they could not tell a child a "homosexual lifestyle" was acceptable.

Dangerous stuff, up their with death threats and so forth.