Well yes, obviously, they would question him and then determine whether or not to charge him. The point is that they couldn't charge him without first arresting him.
Yes, the prosecutor can prosecute the case as they see fit. They're not obliged to question Assange on his own terms.
From the original ruling on the EAW (p. 20):
>Here is it necessary to focus clearly on the facts of the case. Clear and specific serious allegations have been
made against Mr Assange in Sweden. Attempts have been made by the Swedish prosecutor as long ago as
September to interview him. He has not been interviewed. The Swedish system anticipates detention and early
questioning in allegations of this type, but this has not taken place. Mr Assange is not known to have returned to
Sweden since September. I have no doubt that this defendant is wanted for prosecution in Sweden. On the
information before me I cannot say when or what step was taken that can fairly be described as the
commencement of a prosecution. What I can say is that the boundary between suspicion and preliminary
enquiries on the one hand, and prosecution on the other, has been crossed. It may be that after interrogation
and further enquiries the matter will not be pursued. As Ms Ny says, a formal decision to charge is taken at a
later stage in Sweden than it is here. In this jurisdiction a person can be charged with rape or sexual assault by a
custody sergeant and may then wait many months before the case is discontinued. In Sweden the decision to
formally charge is followed very shortly by the trial itself, if the defendant is in custody.
Yes I know the prosecutor can persue the case any way they want to.
I find it odd that you don't understand this, but the point is very simple: if the purpose of the Swedish Prosecutor was to investigate a potential crime, they would have interviewed Assange. Instead they refused to.
>if the purpose of the Swedish Prosecutor was to investigate a potential crime, they would have interviewed Assange.
I don't see how you are drawing this conclusion. There would have been little point in interviewing Assange while he was in the Ecuadorian embassy, since it would not have been possible to arrest him following the interview. More broadly, complying with Assange's demands would also have sent the wrong signal to anyone else trying to escape the justice system.