The family of a 13-year-old boy who died after he was pushed into a river could pursue a private prosecution against the teenager responsible, campaigners have said.

Christopher Kapessa was pushed into the River Cynon in South Wales by a 14-year-old boy in July 2019, but the Crown Prosecution Service decided not to charge the teen and described the incident as a “foolish prank”.

Christopher’s family has accused the CPS and South Wales Police of institutional racism, and on Thursday lawyers representing his mother Alina Joseph will go to the High Court to ask for a judicial review of the CPS decision.

Speaking to BBC Wales Investigates, Suresh Grover of anti-racism campaigners The Monitoring Group, who have been supporting the family, said they would not “give in” if the application for a review is rejected by justices.

“We are not going to give in we will look at everything possible including a private or criminal prosecution,” he said.

“Christopher Kapessa is the acid test for the criminal justice system in South Wales.

“If they fail on this the damage done for the CPS and the police will be irreparable.”

Ms Joseph told the BBC programme, which will be broadcast on Monday evening: “As a mother, you don’t just stop parenting once they have died.

“Christopher is not allowing me to just sit down and give up.

“So even if it is going to take 10 years, 15 years, I just have to deal with it – I have got no choice.”

She added: “I do believe if Christopher was a white child and amongst however many children were there and those children were black the investigation from the get-go all the way to the end would have been very different.”

South Wales Police passed a file of evidence to the CPS, who said there was no “public interest” to bring a manslaughter case against the boy involved despite “evidence to support a prosecution”.

The decision was confirmed in a review carried out by the CPS in July last year after Christopher’s family appealed against the original decision.

A spokesperson for the CPS said: “Our thoughts remain with Christopher’s family following his tragic death.

“We are incredibly conscious when looking at cases involving young people.

“A specialist prosecutor reviewed the evidence and found that our legal test for prosecuting the young suspect was not met.

“Race played no part in our decision making and there was nothing in the statements of the young witnesses to suggest any racial issues or that this was a hate crime.”

BBC Wales Investigates Christopher – The Boy Who Never Came Home is on Monday June 7 at 8.25pm on BBC One Wales and afterwards on BBC iPlayer.