Illinois lets litigants verify pleadings by certification rather than dragging every document to a notary. The trade is explicit: the statute attaches perjury consequences to a knowingly false certification.
Why this matters for prosecutors specifically
Under Kalina v. Fletcher, a prosecutor who personally attests to the truth of facts is acting as a complaining witness rather than an advocate, and receives only qualified immunity for that act. Verification is precisely that kind of attestation.
The documented application
This record contains sworn instruments whose factual assertions are described differently by contemporaneous government documents. See the certification audit and the Kalina line.