A severely disabled child who was forced to go into hotel quarantine after returning from a “red list” country has been allowed to return home to complete their period of self-isolation after a legal challenge.

Before entering the UK, the child’s parents had applied for an exemption on medical grounds, providing evidence of their child’s severe and complex needs, but, having received no decision, they had to enter hotel quarantine on arrival. Their solicitors, Bindmans LLP, said the application was then refused without reasoning.

They made an urgent application to the high court for an order permitting the family to return home to complete the quarantine. They provided further evidence from the child’s treating psychologist of why their particular severe needs could not be met in hotel quarantine and how it would probably lead to a severe deterioration in their condition. After seven days stuck in hotel quarantine, the family won their case.

Theodora Middleton, a solicitor in Bindmans’ public law team, said: “We are pleased that our client has now been permitted to return home. However, it is deeply concerning that highly vulnerable individuals such as our client are being subjected to the hotel quarantine system with little apparent consideration of how it will affect them. Our client and our client’s parents have endured unacceptable suffering, and potentially lasting damage, during the period that they were required to remain at the hotel, and recently updated exemption guidelines set a bar for eligibility for exemption that goes beyond the law.”

She urged the health secretary, Matt Hancock, to “ensure that his newly created and draconian powers to curtail liberty are being exercised with utmost care and scrutiny”.

Under emergency coronavirus legislation, on arrival, passengers entering the UK from “red list” countries are transferred by coach to a hotel where they are required to remain for at least 10 days. They are allowed out of their rooms in “very limited circumstances”, including exercise if granted permission by security guards enforcing the quarantine, with windows reportedly sealed shut.

As well as medical grounds, other exemptions include for people arriving to attend boarding school and representatives of a foreign country.

Bindmans made an application on behalf of its client over the weekend. It said the health secretary was given time to obtain independent medical evidence but did not do so and eventually conceded 15 minutes before a further hearing and three days after being presented with medical evidence from the claimant.

The child’s barrister, Adam Wagner, tweeted: “The system of exemptions for medical need is helpful but only if it is applied reasonably and not, as appears here, raising the bar so high that it is unreachable.”