You're telling the half story.
1) The attacker was prosecuted : Wiens was arrested at the crime scene and subsequently tried for murder and attempted murder. He was found guilty of both charges, with the verdict qualifying the murder of El-Sherbin as a heinous crime because it was committed in front of a child, while attacking another person who tried to intervene.[2] The judge stated that the perpetrator was motivated by hostility and prejudice against a race and religion. Wiens was sentenced to life imprisonment.[2]
2) Officer's shooting the husband wasn't racially motivated: On 29 December 2009, the public prosecutor's office in Dresden announced that all investigations had been closed on 21 December 2009 without indictment,[62] as no suspicion of a criminal offence could be substantiated. Prosecutors argued that it must have been particularly difficult to assess the situation for the intervening police officer,
because when he entered the room "Elwy Okaz and Alex Wiens were both covered in blood and Elwy Okaz had just managed to grab the handle of the knife with his hand, making it appear as though he was the attacker".[63] There were further assessment difficulties because "the actual attackerWienswas holding the blade of the knife, which added to the impression that he was the one being attacked".[63] The prosecutors' conclusion was that shooting of Okaz was a tragic mistake.[64]
I guess you had already made up the mind before you even tried to look for the complete truth. Now try looking for some other excuse for actions of Islamic radicals in Europe.
Murder of Marwa El-Sherbini - Wikipedia, the free encyclopedia