To address the police report, it is meaningless at this point and media reporting is better to go off of. The police only take reports and investigate, but don't comment until charges are filed or the case is dropped. At this stage, regardless of what happened, the police took a report from a self-identified victim. I can report anyone for assault tomorrow, baselessly, and your answer would be to give no credence to the media who talked to the people involved, but rather accept as fact for now that I am a victim because I abused the machinations of power to my benefit.

As for the assault, which I have no doubt happened, we are arguing over the legality of it: People deserve to be assaulted all the time. The person that initiates violence, or otherwise legitimately violates or seriously threatens the physical security of another person deserves to be taught a quick lesson so they can ruminate about personal sovereignty and rights while they heal.

As a general rule, society calls on the strong to protect the weak. Violent people will seek to exploit weaker people. When a violent person errs and unknowingly seeks to exploit a stronger person, it is my opinion that it is the duty of the stronger person in a strong legal and moral position to take the opportunity to perform justice.

Said person doesn't need to know the crimes and transgressions of the aggressor in the past. That the person is now aggressing and violating others rights is enough. If it is the offenders first time, the lesson should hopefully suffice to make it the last. If the aggressor regularly violates the rights of others, it is karmedic justice at a minimum, and true justice if other victims hear about what happened.

TL:DR; it is a moral imperitive to dispense instant karma within the law for those who could not in the past, and cannot in the future.