The brother of murdered private detective Daniel Morgan has accused home secretary Theresa May of stonewalling.
Alastair Morgan held an hour-long meeting with the home secretary in London last week.
Daniel Morgan was found dead with an axe in his head in a London pub car park in 1987, after trying to take a story about police corruption to the News of the World (NotW).
No one has been prosecuted over the killing, despite five police inquiries and court hearings.
Four men were charged in 2008, including his ex-business partner Jonathan Rees and an ex-Metropolitan Police officer Sid Fillery.
But the case collapsed in March.
All four denied any involvement in the killing.
The Met has admitted corruption was a “debilitating factor” in the investigation.
Alistair said, “After two and a half decades of being fobbed off, this meeting has been profoundly unsatisfactory.
“We wanted a full, independent judicial inquiry to find out exactly why there has been no justice for Daniel.
“I think this is another case of stonewalling.
“But we are not going to go away or get tired of it all... watch this space.”
Mazher Mahmood, the NotW’s former “Fake Sheikh”, hired “bodyguards” from Jonathan Rees’s firm Southern Investigations, it has emerged.
Scotland Yard detectives were investigating Rees and his firm for bribing police officers at the time he was working for the NotW as a private investigator.
Rees was sentenced in 2001 to seven years in prison for conspiracy to pervert the course of justice.
When he was released from prison in 2005, Rees was almost immediately re-hired by the NotW.
The paper was then edited by Andy Coulson, who later became David Cameron’s spin doctor.
There is new confusion over who hacked and deleted voicemails on murder victim Milly Dowler’s phone.
Police said they were “most likely” deleted automatically. But they also say there is evidence someone continued to access and delete voicemails over a number of days beyond any automatic deletions.
Milly’s mother discovered messages had been deleted when she rang her daughter’s phone on March 24, 2002.
NotW private investigator Glenn Mulcaire, who admitted hacking Milly’s phone, didn’t access her voicemails until after that date.
But which other people did both hack the phone and delete messages has yet to emerge.