LONDON • The killers were just 10 years old, while the victim was only two.
The incident happened in 1993.
But many people in Britain still remember it and are now upset that Detainment, a movie about that notorious crime, has earned an Oscar nomination in the best live-action short category.
Last week, the Daily Mirror called the nomination an "Oscars insult".
"Hang your head in shame, Hollywood... this is off-limits," read a headline in the tabloid newspaper.
An online petition, calling for the 30-minute Detainment to be removed from the nominations, has attracted more than 150,000 signatures.
Commenting on the controversy, the Academy of Motion Picture Arts and Sciences, which organises the Oscars ceremony, said it was "deeply moved and saddened" by the loss endured by (the victim's) family, but made clear the nomination would not be rescinded.
"The Academy does not in any way influence the voting process," it pointed out.
In 1993, Jon Venables and Robert Thompson were convicted of murdering James Bulger. The images of the two leading James from a mall while his mother was distracted - captured on security cameras - are seared in many people's memory.
The body of James, who was tortured with bricks and a metal bar, was left on a railway line.
When they were released from prison in 2001, Venables and Thompson were granted life-long anonymity. There have been attempts, both legal and amateur, to reveal their new identities.
The killing has already been the subject of a play, which also caused complaints in Britain's tabloids, as well as numerous books.
But none has caused such an outcry as Detainment, which has been accused of humanising or being sympathetic to the killers.
Detainment has won awards, including a special jury prize at Cannes, but started to attract criticism in Britain after it was nominated for an Oscar.
Ms Denise Fergus, James' mother, said: "It's one thing making a film like this without contacting or getting permission from the family, but another to have a child re-enact the final hours of James' life before he was brutally murdered, and making myself and my family have to relive this all over again."
Mr Albert Kirby, a detective who led the investigation into the killing, told the BBC that the events shown in the film were accurate, but still called for its withdrawal from Oscar consideration.
"It's causing so much unnecessary upset," he said.
Vincent Lambe, the 38-year-old Irish director, started researching the murder in 2012. "I wanted to try and understand what could have led two 10-year-old boys to have done this," he said.
There has never been a proper debate about why the killing happened, despite its prominence, he added. He considered contacting the families involved but decided it could harm the film.
"I think if we did contact them, there'd be pressure to tell it the way they wanted it to be told. We never meant any disrespect.
"I hope people can see it with an open mind," he said, "but that might not be possible now."