Before law school, I worked for the Crown Attorney's office (Canadian equivalent to the U.S. District Attorney's office) for several years. My job included the screening and vetting of criminal charges as they came through, advising on the appropriateness and/or sufficiency of the charges laid by the police and the sufficiency or insufficiency of the evidence in support of the charges, making recommendations on increasing or reducing the charges, and making sentencing recommendations on (a) a guilty plea, or (b) a finding of guilt after trial.
I was involved in thousands of plea bargain arrangements during my 5 years there, and it was standard procedure to consult the complainant if the matter was one involving physical violence, threats of violence, break and enters, and other charges that involve complainants in a personal capacity (as opposed to, say shoplifting charges, where we would not consult a department store complainant for input on the plea bargain resolution).
We were not, of course, bound by the wishes of the complainant, but we were obligated to consult the complainant in cases of violence, threats of violence, etc., as directed by the Ministry of the Attorney General and various statutes and guidelines.
We very often reduced charges, or stayed charges, or dropped charges, or had individuals enter into peace bonds and such, and we often sent individuals into various "diversion programs" by which they could escape a criminal record entirely. Each case was dependent upon its own facts, but the wishes of the complainant were always taken into account, even though we were not required to agree with them, or to go in the direction that the complainant wanted us to go. We might disagree with the wishes of the complainant and pursue the course that we thought best served the public despite the complainant, but we did at least consult the complainant. Sometimes a complainant would want all charges dropped and we would disagree and insist upon a plea to some charge or another. Sometimes a complainant would want us to proceed on more serious charges than we felt were warranted, but we would not do so just because the complainant wanted us to do so.
If a case was minor, though, and the accused had no record or a limited record, we were always happy when the complainant was agreeable to reducing charges and limiting sentences.
I have lots of friends and colleagues in the Crown's office, and they still follow these procedures.
The discussion about victim impact statements here is a red herring. That comes later in the process, if it comes at all.