The case of G and H v Upper Tribunal and SSHD  EWHC 239 (Admin) is notable as the first reported case of a successful substantive Cart JR against a decision of the Upper Tribunal (Immigration and Asylum Chamber) refusing permission to appeal from the First Tier Tribunal (FTT) to the Upper Tribunal (termed “an Upper Tribunal permission refusal” in the judgment).
As background, in the case of Cart  UKSC 28 the Supreme Court held that a refusal by the Upper Tribunal of permission to appeal to itself can be judicially reviewed. See this post by Desmond Rutledge for a full exploration of the current rules and procedure in Cart judicial reviews, as they are now known.
The G and H case involved G, a Nigerian woman, who had been trafficked from Nigeria to a “trafficking destination country.” After being forced into prostitution she had eventually escaped to the UK on a false identity, which, when discovered some years later, had resulted in her conviction. While in prison G gave birth to her daughter, H, who is now almost three years old.
By the time G appealed to the FTT against her deportation, she had received a negative conclusive grounds trafficking decision from the National Referral Mechanism, but the decision maker clarified that “The negative decision … was not reached on the basis that [G] was not believed, rather that her claim was historic and that she had been free of her traffickers for a considerable period of time…” G appealed to the FTT on the basis that if she were returned to Nigeria she would be at risk of reprisals from her traffickers and re-trafficking. Her daughter H would be at risk of being subjected to FGM, as G herself had been.
Before the FTT the SSHD conceded that G’s account of trafficking from Nigeria to the destination country was accepted and that the only matter for adjudication was G and H’s risk on return to Nigeria. Notwithstanding that concession, and without putting the parties on notice nor questioning G with regard to her trafficking, the FTT dismissed the appeal after comprehensively disbelieving G’s accepted account of trafficking. The FTT also failed to apply the Court of Appeal’s preserved findings in the country guidance case of PO (Nigeria)  EWCA Civ 132 and dismissed the expert evidence (mostly on the basis that the experts had accepted G’s account whereas the FTT had not).
Grounds of appeal: procedural fairness, expert evidence and country guidance
G applied for permission to appeal to the UT on grounds of procedural fairness, the rejection of the expert evidence without adequate reasons being given and the failure to apply the relevant preserved findings from the country guidance. Permission was refused by the FTT and, upon renewal, by the UT. G then made an application for a Cart judicial review. Permission was granted and, unusually, the SSHD, as Interested Party, requested a substantive hearing.
New guidance on test to be applied in a substantive CART JR
In his judgment Mr Justice Walker gave detailed guidance regarding the test to be applied at the substantive JR stage and the role of the High Court in considering a substantive claim.
Mr Justice Walker found that the relevant test at the substantive stage is whether “an Upper Tribunal FTT permission refusal is vitiated because the Upper Tribunal misunderstood or misapplied the law when holding that the would-be appellant had identified no arguable ground of appeal.”  In other words, there is no need for a Claimant to prove that the FTT committed an error of law, but rather that there was at least an arguable error of law disclosed in grounds of permission to the UT.
With regard to the way in which the High Court would deal with claims of this nature, Mr Justice Walker set out three broad categories of cases, two of which could succeed and one of which could not, because “the would-be appellant’s allegedly arguable ground of appeal is plainly wrong for the reason given by the Upper Tribunal.” . Cases which could succeed include both ones where the “submissions at the substantive judicial review … lead the court to conclude that a ground of appeal advanced by a would-be appellant is plainly right…”  as well as cases in where “the High Court concludes that the allegedly arguable ground of appeal is neither plainly wrong, nor plainly right, but is indeed … arguable.” 
The role of the High Court
In setting out the role of the High Court in these types of judicial reviews, Mr Justice Walker accepted that “…it will often be undesirable for the court to decide a question which the Upper Tribunal may properly be called upon to decide.” However, he went on to find that:
If the matter is properly within the court’s expertise… and a conclusion that the allegedly arguable ground of appeal is plainly right can be reached without making undue demands on court resources, then it may be consistent with the overriding objective to hear argument on the point and decide it. 
In the case of G and H, having examined the grounds, Mr Justice Walker took the view that they fell into the “plainly right” category.
When can a CART JR be consented at the substantive stage?
Another interesting note in this case is the SSHD’s attempt to settle the case part way through the substantive hearing. She proposed a consent order suggesting that the Upper Tribunal permission refusal be quashed because: “It is considered … the most practical resolution”. 
Mr Justice Walker declined to make the proposed order because “It is in my view elementary that a decision of the Upper Tribunal cannot be quashed merely because this is thought to be “the most practical resolution”. 
This is notwithstanding the fact that
CPR 54.7A(9) and (10) have the effect that once permission to proceed has been granted there will, unless a hearing is sought, be a summary determination quashing an Upper Tribunal FTT permission refusal. 
However, Mr Justice Walker found that this remedy was only appropriate where no substantive hearing is sought by the Interested Party because
By not seeking a hearing, as it seems to me, they are in effect conceding that the reasons for granting permission to proceed are reasons which warrant the quashing of the decision under review. 
Practitioners should take heart that the High Court is prepared to find that the UT is plainly wrong, where the circumstances warrant, and not withstanding the well recognized deference to specialist tribunals. In cases where practitioners feel that their grounds of appeal to the UT were either plainly right, or at least arguable, it is worth pursuing those grounds by way of judicial review.