It’s a form of lying, but with a specific meaning.
Like how the 9th (or 8th, depending on how you’re counting) Commandment says to not bear false witness. That doesn’t mean that people following an Abrahamic faith cannot lie… just that they can’t lie in that one specific way.
Parallel construction is a way to present evidence illegally obtained by coming up with a plausible-seeming other way it was found.
So, rather than saying “we illegally stopped and searched the defendant” they’ll get an “informant” (sometimes paid, sometimes coerced) to swear that they tipped them off beforehand.