Nobody is above the law and prosecutor rules and regs.
A prosecutor has to bring charges WITHOUT fear(of being fired, demoted etc), or favor (doing it for personal vendetta reasons, or reasons that help a boss, or help your own political party etc)
A prosecutor can only bring a case to trial, that they are sure they can win. Money is limited, they don't spend tax payer's money for a trial that they think they will lose in a court of law....
Another one of the reasons prosecutors have so many plea deals worked with criminals, is the trial budget is limited, and reserved for big crimes with no plea deals....
Not simply falsifying a statement.