Digwa was also found guilty of carrying a knife in public and his mother, Kiran Kaur, 53, was found guilty of assisting an offender.
Kaur appeared visibly upset in the dock as the verdict was read out, while Digwa showed little emotion and gazed out into the courtroom.
Sobs could be heard at the back of the public gallery, while Nowak’s parents let out a sigh and hugged as they left the room.
Judge William Mousley thanked the jury for their “essential service” in what he described as a “particularly difficult case”.
He added that he was “impressed by the dignity and respect by the people attending”.
