Since agencies are required to publish all proposed and final regulations in the Federal Register, the history of a regulation is consolidated in one place. This is advantageous as it significantly simplifies the process of regulatory research!
If you want to understand the evolution of a particular regulation over time, you can refer to the history information provided on Lexis or Westlaw.
Westlaw Credits Section
On Westlaw, the historical data pertaining to the regulation is categorized under the "Credits" section. By clicking on the Federal Register citation, you can observe how it either initiated or amended the regulations.
Westlaw Example - 8 CFR § 312.1
If you are delving into the historical background of this regulation, you would click on the earliest Federal Register citation (from 1991 in this case) to view the text of the original regulation. Subsequently, clicking on later citations will unveil the evolution of the regulation over the years.
Above, you looked at the history of a single CFR section about literacy requirements for naturalization - 8 CFR § 312.1.
Sometimes you might be interested in not just the current regulation(s) on a topic, but all the regulations there have been throughout history on a topic. If so, you can search a Federal Register database to find the prior regulations on a topic.
Westlaw Example
You can search the Federal Register - All database by keyword and use the PR segment to limit your search so you only retrieve final rules.
