The portrayal of the mentally ill is at the heart of a bitter and unseemly argument between Sane and Mind, two of Britain's leading mental health charities, which has crystallised in the public's mind as the "to drug or not to drug" debate.

Mind accepts that Marjorie Wallace, Sane's chief executive, has propelled the issue of mental illness into the headlines but believes that she has done it in the wrong way. Mind argues Sane has been bad for mental health. Its tendency to focus on the publicity generated by rare cases in which schizophrenics have attacked, or murdered members of the public or greviously injured themselves, has drawn a distorted picture, Mind alleges. As a result people often equate schizophrenia - and other forms of mental illness - with violence.

Liz Sayce, Mind's policy director, points out that 2 per cent of homicides are carried out by people with mental illness, compared with the 60-70 per cent committed by people under the influence of alcohol.

"Sane goes with the grain of public prejudice against people with mental health problems ... It has used the language and images of violence and the failures of community care and it has been very strong. But this has fed the Government response, which has been to tighten up controls on the mentally ill. It has not been about improving services to them."

The issue that forced the fundamental differences into the open, according to Mind, was the high-profile launch of its "Yellow Card" scheme in May. This will allow Mind to collate, analyse and report suspected adverse reactions to psychiatric drugs direct to the Committee on Safety of Medicines, the Government's drug safety watchdog. It has the backing of the Department of Health.

According to Mind, the current system of voluntary reporting by doctors of side-effects has resulted in "massive under-reporting ... and official complacency about the known hazards of established drugs and about the adverse effects of psychiatric medication generally".

It was this scheme, Mind says, that incurred the wrath of Ms Wallace, and prompted her to lobby eminent doctors to sign the letter that was subsequently published in the Independent in early June.

Mind denies that it is "anti-drug", but believes that powerful, neuroleptic drugs, which can have distressing side-effects, are prescribed in excessive doses and dangerous combinations by some doctors who know little about them. Each year 3,000 people call the MindinfoLine, anxious about drug side-effects. The charity is campaigning for more research into the effects of these drugs, and has lobbied the Government to include deaths linked to neuroleptic drugs in its confidential inquiry into homicides and suicides.

Liz Sayce acknowledges that Mind's repeated claim that one death a week caused by these drugs is an informed estimate (attributed to Professor Malcolm Lader at the Institute of Psychiatry, London) but argues that circumstantial evidence suggests that when the research is completed, the figure will prove an underestimate.

Ms Sayce questions Sane's use of government statistics. Sane has claimed that 100 people a year are murdered by the mentally ill. Mind's reading of the same report is that the figure is nearer 12.

"Why is it anti-drugs to provide information about drugs?" Ms Sayce asks. "We believe in informed choice and that people are more committed to taking drugs if they know what is going on." But, she says, drugs alone are never enough. "A psychiatric drug does not amount to care in the community."