The Crown Prosecution Service refused to bring charges against the constable, saying that the alleged assault on John Campbell was not serious and in any case the officer could be punished at a Metropolitan Police disciplinary hearing.
The hearing was set for 31 March this year. The constable was accused of being drunk on duty, using unnecessary force, and being abusive to two sergeants, the Police Complaints Authority said. But he was taken ill and the hearing was postponed. Last week Mr Campbell was told that it would never take place: a letter from the Metropolitan Police told him that 'the officer (has) retired . . . and disciplinary proceedings are therefore cancelled.'
Mr Campbell, who works for an Aids charity, said: 'My lawyers tell me my only option now is to sue the police for damages in the civil courts. But it will take 18 months for the case to come to court. By then I will almost certainly be dead.'
The case began in June 1992 when police were clearing Oxford Street during a bomb alert. Mr Campbell, 25, was returning home after visiting a friend who was dying of Aids in a nearby hospital. Mr Campbell was upset and very weak; since being diagnosed HIV positive in 1987, he had suffered five attacks of pneumonia and developed meningitis, stomach infections, the muscle-wasting disease myopathy, and sinusitis. His teeth had begun to crumble and at times he was finding it difficult to walk.
He says that he was waiting for the all-clear when he saw a man in plain clothes letting a woman through a barrier, which had been preventing access to cordoned-off streets. 'A group of us began to move across the road because we thought the alert was over. The man on the other side ran up to me screaming and shouting.
'He grabbed me by the lapels and shook me. I fell back against a street sign-pole and was then picked up and thrown into shop shutters. I slumped to the floor and blacked out. When I came to he was shouting at me, 'I fucking warned you to get back to the other side.' '
The Police Complaints Authority confirmed that the constable, who was in plain clothes, was then taken into custody by fellow officers. Statements were taken from other officers and members of the public. Mr Campbell booked himself into hospital and was prescribed painkillers to cope with internal bruising.
'I was very frightened and shaken,' he said. 'But the CPS later told me that the severity of my injuries 'did not warrant' a prosecution.
'I thought it would be sorted out at a disciplinary hearing. Now there won't be a disciplinary hearing either. I'm more angry with the system than with the officer. I was in prison on homosexual prostitution offences when I was first diagnosed HIV positive and I know that, even when a member of the public has one of the worst conditions there is, he cannot get out of jail.
'I'm not vindictive, but I will pursue a civil case against the Metropolitan Police, rather than the officer, for as long as I can, just to highlight the principle that policemen should be answerable for their actions.'
Police Complaints Authority sources said that they sympathised with Mr Campbell, but added that the officer had taken early retirement, and thus avoided a disciplinary hearing, because he was genuinely ill.
In its letter to Mr Campbell telling him no action would be taken, the Met said that it 'regretted that the officer in this case fell short of the high standards expected of the Metropolitan Police', and apologised.