Prosecutorial Vindictiveness v. Malicious Prosecution
The following is not legal advice but is for information only. Legal advice is when an attorney applies the law to a person's individual circumstances and advises them on their legal options or potential exposure to legal harm, which a web page clearly does not.
Prosecutorial vindictiveness and malicious prosecution appear to be the same but are very distinctly different legally. One involves a motion for a remedy based on criminal charges during and after a criminal proceeding (such as a new trial). The other is a civil tort, or claim for damages, that needs a lawsuit.
Prosecutorial vindictiveness is grounded in the constitution’s principle of due process. It occurs when a prosecutor retaliates against a defendant for exercising a constitutional or statutory right - such as increasing the number or severity of the charges against them. Burdens of proof can differ, depending on whether a case has never had a trial or a case has been overturned on appeal.
Prosecutors get broad discretion while a case is pending. However that discretion is not unfettered. If there is actual proof that, say, a prosecutor indicted someone on a felony after they litigating a motion to suppress evidence on a misdemeanor, that could be grounds to dismiss the new charges or even the entire case. If a case wins on appeal and a new trial is held, increases in number or severity of charges at the second trial creates a presumption of prosecutorial vindictiveness that the government must rebut if raised by a defense attorney. The same constitutional principle (due process) applies to a judge’s sentence which cannot be more severe for using a right (such as going to trial) - without a reasonable and well-grounded justification placed on the record.
Needless to say, vindictiveness by a prosecutor that punishes use of a right is very difficult to prove - particularly before a trial - but it has been done. Recent examples in in other jurisdictions include demonstrators who wanted a trial who were then charged with an additional count (that led to dismissal of the whole case not just the new charge), dismissal of charges brought because a defendant changed the trial venue, or a new trial for a defendant who rejected a plea deal and new charges were brought without any new developments or evidence. Facts in those instances pre-trial were clear. However, it is rare.
On the other hand, malicious prosecution is a civil legal claim known as an intentional tort. This is when a person brings a legal action or criminal charges that weren’t true or legally justified for the purpose of causing harassment - or really any purpose that does not involve the merits of the action (the civil claim or criminal case). Prosecution in this context is really more literal in meaning ‘bringing a court claim’ (prosecuting) than involving a prosecutor. Generally that means a false or groundless allegation or legal claim that is made by witness (a malicious neighbor or former partner for instance). Prosecutors are (rather ridiculously) given near complete immunity for civil claims because of sovereign immunity that originated in England and because claims could not be brought against a King - the sovereign - who could do no wrong. This doctrine about monarchy has been upheld by the United States Supreme Court in a republic founded on opposition to monarchy. Police officers are also covered by a partial immunity based on this doctrine and are extremely difficult to sue.
So, malicious prosecution involves someone being sued or who is criminally charged based on false allegations or bogus legal claims. It is not about an assistant district attorney or assistant attorney general during a pending criminal case.
To win a civil claim for malicious prosecution, a person has to have been harmed, the person who was in the wrong had to have substantially caused the harm, and the person harmed had to have won or prevailed (with, say, a dismissal, a win at trial or a not guilty), among other factors.