A male nurse who was sentenced to life imprisonment for the murders of 22 elderly people in Switzerland has started an appeal against his conviction.

The man, dubbed "the Angel of Death", was at the centre of one of the worst cases of serial killing in the country's recent history. The hearing is taking place in Lucerne cantonal court.

A verdict is expected up to two weeks after Thursday's hearing.

The 37-year-old nurse was convicted of 22 murders and attempting to kill five people in January 2005 but was acquitted of two further charges of murder and attempted murder.

His victims, mainly elderly women, were all residents at care homes in the central cantons of Lucerne, Obwalden and Schwyz between 1995 and 2001. They were aged between 66 and 95 and many were suffering from senile dementia.

An investigation concluded that the nurse killed his victims with tranquilisers or by suffocating them.

At his trial, which caused huge media interest in Switzerland, the man explained that he had acted out of compassion and wanted to release the victims from their suffering.

Rejected

But judges at Lucerne's criminal court rejected his arguments, handing down a harsher sentence than the 17 years demanded by the prosecution.

In a written judgement, published in May last year, the court said that in reality the accused couldn't cope with the amount of work and had tried to lessen the load.

It said he had acted purely out of selfish reasons and had "played God" showing a total absence of morals or scruples.

Furthermore, the nurse had killed in a " treacherous and violent" manner.

Judges said that in this case the 22-year sentence was justified, despite the nurse's collaboration with the justice authorities and willingness to have therapy.

But on Thursday the man reiterated his claims that had acted out of compassion. His defence lawyer added that his client was not unscrupulous or out of touch with reality.

But the prosecutor continued to cast doubt on these arguments. He called for the life sentence or a 17-year-sentence to be maintained.

Suspicious

The nurse was arrested in June 2001 after the authorities became suspicious about the high number of deaths at a special unit for the senile in Lucerne, where he had worked for six months.

Following his arrest, investigators widened their probe to include other homes and hospitals where the man had been a staff member. Five bodies were exhumed as part of the investigation.

Police traced 12 suspicious deaths to one home for the elderly in the nearby town of Sarnen in central Switzerland.

Apart from receiving a life sentence, the nurse was also ordered to pay SFr75,000 ($63,000) in compensation to the relatives of four of his victims and court costs of SFr191,000.

swissinfo with agencies

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