IIUC, and I may not, that's slightly too strong and there are some circumstances where evidence that's (shall we say) barely inadmissible doesn't necessarily in

IIUC, and I may not, that's slightly too strong and there are some circumstances where evidence that's (shall we say) barely inadmissible doesn't necessarily invalidate later evidence. But in any case, whether the principle applies to a given instance is something that needs to be tested in court, and parallel construction is deliberately depriving the court of the ability to make a determination.