The phrase "wronged party" refers to a person or group of people who have been treated unfairly or harmed by another person or organization. Full definition
When a mistake is more than a minor setback, do something to make it right or otherwise provide value to the wronged party.» (inc.com)
This means anything from a court proceeding that mentions your name to a police blotter from college for being at the wrong party at the wrong time. (entrepreneur.com)
I was appalled when the CNN reporter said out of the blue «wrong party» on TV. (religion.blogs.cnn.com)