from Wiktionary, Creative Commons Attribution/Share-Alike License
- Used other than as an idiom: bang (adverb), to rights.
- v. To have sufficient, undisputable evidence that a person's actions are generally perceived to be wrong; to catch red-handed.
From reinterpretation of bang ("completely") + to rights ("properly") (Wiktionary)
From reinterpretation of bang ("completely") as bang ("to handle noisily or violently") (Wiktionary)