Legal ethics and professional responsibility are governed by rules, cases, and ethics opinions.  The rules can often be found in an annotated code.

Many states follow the previous or current model rules of professional conduct. You can usually find the rules within a print annotated code.

Bluebook

Rule 12.9.6 of the Bluebook (19th ed.) covers the citation of the ABA Model Rules.

Elements

The citation should include the following:

• Source
• Rule
• Year adopted (unless the version cited includes subsequent amendments, then give year of  last amendment)

Example

Practitioner typeface:

Model Rules of Prof'l Conduct R. 1.5 (2009).

Scholarly citation typeface:

Model Rules of Prof'l Conduct R. 1.5 (2009).

ALWD

Rule 27 of the ALWD Citation Manual (4th ed.) covers the citation of restatements.

Elements

The citation should include the following:

• Title 
• Rule
• Organization
• Date

Example

Model R. Prof. Conduct 1.5 (ABA 2011).

The American Bar Association promulgates model ethics rules. These rules are not binding law in any jurisdiction unless affirmatively adopted by the legislature of that jurisdiction. Many states follow the previous or current model rules of professional conduct in some fashion.  You can find the model rules in print on reserve but you can also find them on Lexis, Wesltaw, and in the ABA / BNA Lawyer’s Manual.