This is the answer most people find hardest to accept. In Bordenkircher v. Hayes, the Supreme Court upheld a prosecutor’s explicit threat to seek a far harsher charge if the defendant refused to plead. Hard bargaining, the Court held, is inherent in a system that depends on pleas.
Where the line actually sits
Vindictive prosecution doctrine prohibits penalizing a defendant for exercising a protected right. Distinguishing lawful leverage from unlawful vindictiveness turns on context — the strength of the underlying case, the disclosure history, whether new charges appeared after the right was exercised, and what followed.
Why written examples matter so much
The mechanism is almost always oral, so appellate courts rarely see it. A written statement is unusual and permits the analysis to proceed on documents rather than recollection.
The documented example
A Lake County prosecutor wrote on June 12, 2025 that a trial would revoke the offer and bring a prison request if the State prevailed — in a case where the investigating detective had already written that the drug proof was thin. See the email.