To think this sounds like bollocks a appreciate anyone with a police background to clarify

[WeetabixTowels]

Say somebody violently attacks a person, is arrested and claims it was all in self defence - because the victim was coming at them with a knife. And they say they’d like to press charges against the victim. The police bail them without charge, pending an investigation. The attacker is told by police ‘You can counter prosecute the victim once the investigation against YOU is over, and not before that’.

AIBU to think this is bollocks and never happened?

And yes I know only police and CPS can press charges, not victims - which adds to my doubt about the whole entire story.

And those were apparently the exact words used

I don't know and am sure someone more knowledgeable will answer but surely everyone just needs to wait for the investigation to conclude.

I am not sure that self defence works if the victim is badly hurt as the violence against them went beyond defence.

I mean - you surely wouldn't be able to counter prosecute if your case stood no chance of success due to lack of evidence.

Sounds like bollocks to me.

Police will investigate and decide who to charge with what, could be both of them, one of them, neither of them. Not the choice of those arrested. Police don't have to charge immediately though

Bollocks.

It'll one of them invisible/magically evaporating knives, I take it.

CPS decide to 'press charges', not the victim for a start.

What we're talking about here is a counter allegation. The original investigation will take precedence, the police will investigate and decide if there is sufficient evidence to take to cps. Once that's dealt with, if the original suspect is making an allegation that they were actually the victim, they can request to make a statement. The investigation evidence is likely to be the same as the original investigation as the statement will surely say what they said in interview when they were a suspect.
They don't decide if anyone gets charged though.