There are number of places to consult when researching legal ethics and professional responsibility.
Model Rules including ABA Model Rules and states' model rules.
Statutes and Rules and Regulations include statutory text and rules and regulations enacted by the body designated in the statute.
Ethics Opinions include restatements of laws and rules providing better understanding.
Case Law includes legal ethics judicial opinions including state or federal case law.
Scholarly Writings include law reviews that regularly publish scholarly articles on professional responsibility, and introductions, treatises, and handbooks.
Newspapers, particularly legal press covering stories relating to professional responsibility.
Online or website sources include organizations, associations, law firms, commercial sites, or blogs.
Attorneys' conduct is governed by rules of legal ethics and professional responsibility adopted by each state. The American Bar Association (ABA) adopted Model Rules of Professional Conduct in 1983. Before the adoption of the Model Rules, the ABA model was the 1969 Model Code of Professional Responsibility. Preceding the Model Code were the 1908 Canons of Professional Ethics (last amended in 1963).
The ABA Model Rules have been subject to a number of changes over the years based on recommendations of standing committees. In 2002, the Ethics Commission conducted a review of the entire Model Rules and the Commission on Multijurisdictional Practice adopted changes to rules 5.5 and 8.5. Further in 2002, the Standing Committee on Ethics and Professional Responsibility adopted changes to rules 7.2 and 7.5. In 2003, the Task Force on Corporate Responsibility adopted changes to Rules 1.6 and 1.13. In 2007, the Standing Committee on Client Protection adopted changes to rule 5.5 comments. In 2008. the Criminal Justice Section suggested changes to rule 3.8. And most recently, in 2009, the Standing Committee on Ethics and Professional Responsibility adopted changes to rules 1.0 and 1.10. To access individual amendments, click here.
Individual states more or less adopt the ABA Model Rules, except the state of California, which is the only state that does not have professional conduct rules that follow the format of the ABA Model Rules.