ring in v.1
1. [early 19C+] to substitute fraudulently, e.g. one racehorse for another.
2. [mid-19C+] (US) to gain admission, to force one’s way in, to impose.
3. [late 19C–1920s] to tell lies, to deceive.
4. [20C+] (Aus./US, also ring on) to involve someone in something fraudulent; to subject someone to fraudulent acts.
5. [1900s] to involve.