Is the case only about consent on the part of the child?
I think it is OldCrone. My understanding is they are asking GIDS to stop giving children these drugs because they cannot give informed consent. That's the bit of law they're using to bring the case.
It seems a bit topsy turvy putting all the emphasis on the child and their capacity to consent when of course they should just stop this treatment anyway, whether children can consent or not, because it's so deeply unethical. I can't think how else to challenge it though, except for waiting for those already harmed to take on the burden of legal action as they grow older and experience regret. That option will still be there in the future if this challenge fails.
On the informed consent thing - I understand the threshold for capacity is very low but what about the 'informed' bit? According to the HRA page, GIDS' study stopped recruiting in 2014, so children given blockers now are not part of any study or trial. But GIDS still doesn't have any answers. They don't know why this completely new cohort are flocking to them in such huge numbers and they don't know what the outcomes are - obvs a near 100% progression to cross sex hormones and sterility and loss of sexual function, but in broader mental health terms they don't even know if this treatment improves outcomes for 'genuinely trans' children. Early signs are not promising.
Are the children 'informed' that GIDS are basically winging it? If they are, then is 'we don't know, knobody knows!' sufficient information for anybody of any age, outside of a clinical trial? Especially while bogus suicide stats are being bandied around so freely. Children become convinced that if they don't have this treatment they will be at extremely high risk of suicide. To be clear it's not GIDS plugging the phoney suicide stats but it's worth questioning how much they are doing to counteract that narrative when discussing treatment with these children.
'don't know' vs. made up risk of death
Looks like misinformed consent to me, regardless of the patient's age or capacity. I'm not even a pretend lawyer though, so ...