The process was set to begin on Thursday, but the man’s defence team filed a claim accusing one of the court lay assessors of being biased.
In Germany, such assessors help criminal courts make decisions on points of law and fact, along with professional jurists.
The defence team said that the assessor wrote letters to the editor in a newspaper, complaining about criminal youth with immigrant roots. The defendant is a 28-year-old Bulgarian man.
The court must now decide whether the woman is in fact biased, and thus whether they must find a replacement assessor. If they do decide to find someone new, this could take several more weeks before the trial would resume again. The court is set to reconvene on Tuesday.
Immediately after the crime, police searched in vain for the attacker. But after weeks without an arrest, they made the unusual decision to publicly release video footage of the attack.
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By mid-December, they had detained a cousin of the suspect who also appeared on the CCTV footage, and officials then believed that the main suspect had gone into hiding in his Bulgarian homeland.
But shortly before Christmas, the suspect was arrested at Berlin’s central bus station after he arrived on a long-distance bus from southern France.
The charge of grievous bodily harm entails a sentence of anywhere between six months and ten years in jail. The defendant also has several charges of theft and driving without a licence in Bulgaria, and has reportedly admitted to police that he committed the crime.
The 26-year-old victim, who suffered a broken arm and head injuries in the fall, is a co-plaintiff in the case.
Prosecutors say that the attack “had the potential to endanger her life.”
The defendant faces a further charge of public exhibitionism. Prosecutors allege that he masturbated in front of two women in the middle of the day in the Reinickendorf neighbourhood of Berlin two weeks before the violent assault. He then repeated this crime in front of another witness around 35 minutes later.