Judge Sebastian Bührmann on Thursday morning called Niels Högel's killing spree “incomprehensible”. The 42-year-old murdered patients selected at random with lethal injections between 2000 and 2005 until he was caught in the act.

Högel was charged with nearly 100 murders, 43 which he confessed. In 15 cases, the court acquitted him.

On the final day of the trial on Wednesday, Högel asked his victims' loved ones for forgiveness for his “horrible acts”.

“I would like to sincerely apologize for everything I did to you over the course of years,” he said.

The heavy-set Högel, 42, has already spent a decade in prison following a previous life sentence he received for six other murders. 

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According to the charges against him during this, his third murder trial, Högel had been accused of killing 97 patients aged between 34 and 96 by medical injection in hospitals in the northern cities of Oldenburg and Delmenhorst.

His horrific killing spree is believed to have begun in 2000 and only stopped when he was caught in the act in 2005.

Driven by a desire to show off his skills in bringing patients back from the brink of death, Högel repeatedly gambled with the lives of vulnerable victims chosen at random.

Most often, he lost.

The exhumation and autopsy of more than 130 bodies were necessary to build
the case for the prosecution.

Police suspect that Högel's final toll may be more than 200. But they say they can never know for sure because of gaps in his memory and because many likely victims were cremated before autopsies could be performed.   

'Always ready to lie'

Caught in 2005 while injecting an unprescribed medication into a patient in Delmenhorst, Högel was sentenced in 2008 to seven years in prison for attempted murder.

A second trial followed in 2014-2015 under pressure from alleged victims' families.

He was found guilty of murder and attempted murder of five other victims and given the maximum sentence of 15 years.

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At the start of the third trial in October, Bührmann said its main aim was to establish the full scope of the killing that was allowed to go unchecked for years.

“It is like a house with dark rooms — we want to bring light into the darkness,” he said.

Victims' advocates say the court has failed woefully at the task, due in large part to Högel's own contradictory testimony.

After admitting on the first day of testimony to killing 100 patients in his care, he has since revised his statement.

He now says he committed 43 murders but denies five others. For the remaining 52 cases examined by the court, he says he cannot remember whether he “manipulated” his victims — his term for administering the ultimately deadly shots.

“That leaves people in the dark — it doesn't allow them to mourn,” Petra Klein of the Weisser Ring crime victims' organization in Oldenburg told AFP

She described the legal proceedings as “trying” for the loved ones.

Psychiatrist Max Steller told the court that while Högel bears responsibility for his acts, he suffers from a “severe narcissistic disorder”.

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He “is always fundamentally ready to lie if that allows him to put himself in a better light”, Steller said.

The defendant claims, for example, not to remember his first victim, who died on February 7th, 2000.

However a serial killer never forgets his first victim, Steller asserted, “meaning that he probably 'manipulated' before that”.   

'Collective amnesia'

While former colleagues in Delmenhorst admitted to having had their suspicions about Högel, all the staff from Oldenburg who testified said they were oblivious to the body count stacking up on his watch.

Bührmann appeared exasperated by what he called this “collective amnesia”.

Ten of the witnesses are now facing possible charges for perjury, according to a spokesman for the prosecution.

Klein said that, at this point, the biggest hope of the victims' families was that Högel “should never emerge from prison”.

She said the idea that he would one day walk free — which is not inconceivable under the German justice system, in which life in prison means 15 years with the possibility of an extension — would be “unbearable for many of them”.

By Isabelle Le Page