Parents shocked by the sudden closure of a residential unit at a special needs school in Bristol, which resulted in children with severe and complex learning difficulties having to move out, have won legal aid funding to investigate a possible challenge to the lawfulness of the decision.

Parents were called at work and summoned to pick up their children from St Christopher’s – an independent special school and residential care home in Westbury Park, in the north of the city – after Ofsted suspended its registration due to safeguarding concerns.

Police confirmed at the time they were investigating allegations of child cruelty and a number of staff were suspended pending the outcome. Parents expressed anger at the way the closure, which happened three weeks ago, was handled and sought legal advice.

Kevin Maxwell, whose 16-year-old son Jonah was one of around 30 pupils moved out of St Christopher’s, has been granted legal aid funding to investigate potential claims resulting from the closure. Jonah is now living at home.

He said: “We remain extremely concerned about the closure of St Christopher’s and have instructed [the law firm] Bindmans to investigate the lawfulness of the decision. Along with the other families involved, the closure continues to have a significant impact on both our son and our family. Given the extent of Jonah’s autism, it simply can’t be in his best interests for the doors of his home for the past six years to be shut as abruptly as they were.”

A statement from Bindmans said: “We have been instructed by the Maxwells to advise on the lawfulness of the actions and decisions that led to the sudden closure of the residential unit at St Christopher’s.

“The Maxwells have been granted a legal aid certificate which will allow them to investigate any potential claims in respect of that sudden closure. The next step will be to provide the Maxwells with formal legal advice. Unfortunately, such advice can only properly be given on a confidential and legally privileged basis and we are therefore unable to speculate as to what such claims might involve.”

At the time of the closure, Ofsted said the residential unit at St Christopher’s had been inspected in June and was judged inadequate. “On Monday 29 July, we issued St Christopher’s with a suspension of registration notice because of serious concerns about safeguarding.”

St Christopher’s is run by the Aurora Group, a private company specialising in special education care. An Aurora spokeswoman said at the time: “We are deeply concerned about the serious allegations against a small number of staff who were immediately suspended. We are now focused on doing all that we can to support the children, young people, their families and carers, and the many caring and dedicated staff who are affected during this difficult time.”

Ofsted later said it was confident it made the right decision. “That is because in July we were made aware of new significant concerns about child cruelty, which now form part of a major ongoing police investigation. We only take such decisions to suspend children’s homes registrations when there is a reasonable belief that any children may be at risk of harm – this test is set out in law. The decision was also taken after strategy meetings with other agencies, which shared our concerns.

“We understand the distress this caused to the families involved, but it is important that we take swift action where we have serious concerns about children’s safety. When children’s homes close it is up to local authorities to find suitable accommodation for children in care, and we always work with them during this process.”

According to Ofsted, St Christopher’s school has been inspected seven times since it was registered in 2016 and has never been graded better than “requires improvement”. In June, it was inspected and judged to be inadequate for a second consecutive time. “Following this inspection we took steps to restrict more placements at the home and served a notice of proposal to cancel registration. Following the decision to suspend, St Christopher’s school did not appeal the decision and chose to voluntarily cancel its registration.”