Comment by wat10000
I strongly disagree. The victim is generally deeply incapable of being objective about the situation. How many perpetrators of domestic violence would go free because their spouse is too scared to ask for proper punishment? This is already a big problem with securing cooperation for prosecution, and I'd aim to make that better, not worse. You'd have enormous disparities in sentencing based on the personality of the victim. Should mugging a vindictive asshole carry a harsher sentence than mugging a nice person who believes in second chances no matter what?
The justice system is pretty far from actual justice in many cases, but this wouldn't get it closer.