Victim of art

As I plunged the sponge into the soapy bucket to clean my wife's car I noticed a large area of white and blue on what should have been a red offside bumper area. I naturally assumed I or my wife had scraped a post or another car but we would have noticed it. A gentle rub showed that the white was powder paint and the blue was a water-based paint. There are no deep scratches but a few areas where spots of red paint are missing. Wife is furious, more so when I tell her it is only a metal box...