Christopher Kapessa, 13, could not swim when he was pushed into the River Cynon in Mountain Ash, Wales, in July 2019.
Prosecutors chose not to prosecute a 14-year-old boy over the schoolboy’s death ruling it as a “foolish prank”.
But Christopher’s heartbroken mother Alina Joseph believes he was denied justice because he was black – alleging police had failed to act on previous racist abuse the family had suffered.
She said that on the day of his death, Christopher told her he was going out to play football with friends.
But a man later came to her door telling her to “come quick, come quick” as her son “had jumped” from a bridge.
She said: “The guy was trying to explain to me Christopher could not be found and I could see helicopters.”
Ms Joseph rushed to the River Cynon but there was no sign of her son and she was told to go home.
The hearing was told her son had “basic” swimming lessons with school but was not a confident swimmer.
Ms Joseph was later taken to hospital by police but says she was given no information by police or hospital staff.
She said: “I was walking around like a crazy mum telling them to tell me where my son was.
“Nobody told me Christopher had died until I worked it out for myself.
“There are no words to explain how I felt, no words to describe how this has left our family.”
In a statement to the inquest, she described Christopher – who loved playing football and computer games – as “my treasure” who gave her “strength in life”.
She said: “Life will never be the same after Christopher’s death. I will continue to fight for justice for him.”
Mother-of-five Ms Joseph said the family moved from London to Wales into a refuge after domestic abuse.
But she said one of her sons had been “badly beaten up” and another was “run over” after a woman was unhappy with him talking to her child.
She said one time Christopher had been left in a “pool of blood” after playing with friend but said he had no idea how it had happened.
She said: “This time I didn’t bother calling the police because I had given up calling them.
“The family ceased to make calls to the police in respect of racist abuse because we were unsatisfied with the response on every prior occasion.”
She told the hearing Christopher had enjoyed: “A loving upbringing with love, discipline, protection, education, listening and understanding.”
The court heard assistant coroner David Regan address Ms Joseph on how difficult the inquest may be for her, as it was Christopher’s 18th birthday two days ago.
After a CPS review on the decision not to prosecute the 14-year-old, chief prosecutor Jenny Hopkins said: “Although there was evidence to support a prosecution for manslaughter it was not in the public interest to prosecute.”
The family challenged the review but it was upheld by the High Court in 2022.
The hearing, at Pontypridd Coroner’s Court, is expected to last two weeks.