The court's decision is expected to set a guide for lower courts across Canada, who have handed down mixed rulings on police responsibility when they finger the wrong person. The Supreme Court is tackling the issue at a time when there is growing concern internationally about the plight of the wrongly convicted.

Jason Hill, of Hamilton, Ont., contends the local police violated his constitutional rights by failing to re-investigate his case in the mid-1990s, despite mounting evidence of his innocence.

''There is a simple question at the heart of the appeal,'' Hill's lawyers, Louis Sokolov and Sean Dewart, say in a written court brief.

''Where substandard policing causes a miscarriage of justice, should the victim be able to obtain compensation from the police service which caused his or her losses?''

The Hamilton-Wentworth police force counters, in a court brief, that imposing legal liability for negligent investigations ''is inconsistent with the long-established principle that police owe a duty to society as a whole, not to any particular member thereof.''

Hill was 26 years old when he was charged with 10 counts of robbery following a police investigation in 1994 and 1995. He was convicted on one count and he spent 20 months in jail before his conviction was overturned on appeal.

He was later cleared in a new trial.

Police maintained they had the right man even when the bank robberies continued, while Hill was in jail, and they received fresh evidence from an anonymous tip two days before Hill's arrest, which eventually led them to the true thief.

When he was freed, Hill filed a lawsuit against the Hamilton-Wentworth police force, alleging malicious prosecution, negligence and breaches of his Charter rights.

One of his complaints was that witnesses were asked to identify him from a photo-lineup that included one aboriginal person and 11 photos of Caucasians, which singled him out, especially when police were looking for a man with dark skin.

''This case has many of the usual ingredients of a wrongful conviction,'' say his lawyers.''

Among other things, police ''solved'' the case by jumping to conclusions, the accused was a member of a racial minority who was falsely identified by unreliable eye witnesses, and police wilfully ignored any evidence that didn't fit their theory, says Hill's legal brief.

His lawyers further assert the ''law of negligence must be brought to bear on the problem of wrongful convictions'' to keep police tactics in check.

The case is drawing several intervenors on both sides, including the Canadian Police Association, the Canadian Association of Police Chiefs, the Association in Defence of the Wrongly Convicted and the Canadian Civil Liberties Association.

Police contend the stakes are high in the case and the outcome could change the course of police probes.

''If simple negligence is all that is required for an individual to be able to recover damages from the police, it is only logical that police officers and police agencies will allow the threat of civil liability to influence their decisions in investigating criminal offences and charging suspects in undesirable ways,'' says a court brief from the Canadian Association of Police Chiefs.

Hill's lawsuit was dismissed in the lower courts, which found the police did not act maliciously and genuinely believed Hill was their man.

''The Court is sensitive to the damage that Mr. Hill and his family have suffered, both by the wrongful conviction and the time Jason Hill spent in prison,'' Justice David Marshall, of the Ontario Superior Court, wrote is a 2003 ruling.

''They have suffered a great deal. However, it is not every wrong that the civil law can right.''

The Ontario Court of Appeal upheld the decision by a 3-2 margin.