Today marks the 50th anniversary of what racial justice campaigners have described as one of Yorkshire's most shameful episodes.
Nigerian immigrant David Oluwale had come to Britain to work, at 19 years old sailing into Hull on a cargo ship. But mentally ill and vulnerable he ended up homeless in Leeds.
Mr Oluwale never settled, and spent his time in and out of prison, on the streets in Leeds City Centre, and at the infamous High Royds psychiatric hospital in Menston.
After his release he was targeted by two Leeds Police officers and was systematically beaten right up until his death in 1969.
Since his death he's been held up as the first victim of racist policing, an immigrant from Nigeria who was easy prey.
The 38-year-old Nigerian immigrant has become a part of Leeds. When he was buried - the only people there to mourn were the undertakers. His death burns deep into the conscience of this city.
In April 1969, Oluwale was seen running towards the River Aire. He was holding the back of his head with his hands.
On 4th May his badly beaten body was pulled from the water.
His death brought an end to his torment but it marked the beginning of one of the most shameful periods in the history of the police in Leeds. The mentally unstable man had been abused both physically and mentally by those whose very job was to protect.
Those men were Inspector Geoffrey Ellerker and Sergeant Kenneth Kitching.
Oluwale drowned after and he was trying to avoid a further beating, the river he thought, was his only escape.
The officers were charged with his manslaughter, but, in a controversial direction by the judge, they were acquitted in November 1971.
Nevertheless, based on the evidence of Police Cadet Gary Galvin and his contemporaries the two officers were convicted of assaulting Oluwale. But Ellerker and Kitching were only given short jail sentences. Ellerker received 36 months and Kitching 30 months.
Policing has changed over the years, but five decades later the family of another black man who was unlawfully killed in police custody in Yorkshire say there are still lessons to be learned.
For racial justice campaigners Janet Alder and Ruth Bundey there are striking similarities between the death of David Oluwale and the fate of Janet's own brother.
Christopher Alder's death in April 1998 in a Hull police station became one of the most controversial in police custody, when CCTV was recovered showing the father-of-two gasping for air as officers chatted and joked around him.
It took 11 minutes for him to stop breathing and as he lay dead, monkey-like noises were heard on the audio tape. He was unlawfully killed an inquest ruled, but five police officers accused of manslaughter walked free on a judge's orders.
Christopher Alder is one of 178 black and minority ethnic people who've died in police custody in England and Wales over the last three decades. That equates to 14 per cent of all deaths in police custody and that's proportionate to the population as a whole.
But the proportion of black people as opposed to say white people dying after the use of force or restraint in police custody is much much higher.
David Oluwale family are unknown but for Janet Alder the death of her brother was only the start of years of trauma.
In 2011 Christopher's body was found in the mortuary at Hull Royal Infirmary, eleven years after his family believed they had buried him. In fact his body had been swapped with that of 77 year old Grace Kamara. - and . Christopher's remains had been used for training without the family's knowledge. Then it emerged that Humberside Police had placed Janet under surveillance during her brother's inquest.
13 years after Christopher Alder's died , the Government apologised to Janet on behalf of Humberside Police. West Yorkshire Police which took over from the Leeds City Police force in 1974 says a case like David Oluwale could never happen now.
But the police chief in charge of diversity in the country last year acknowledged there was still institutionalised racism within the ranks of the police.
For Janet Alder change can't come soon enough.