Writing on an issue where the federal circuits have differed on their resolution of a legal issue is traditional fodder for journal articles and papers. Split circuit decisions can only be resolved by the United States Supreme Court, and an article about the split will add an important and timely voice to the scholarship on the topic.
Bloomberg Split Circuits Chart
This is available on Bloomberg Law in Law Review Resources and is an analysis of federal circuit court splits. Access requires a UB Law Password. Updated monthly
Seton Hall Circuit Review (2005- 2019): This law review contains a "Current Split Circuits" column arranged by topic. This journal is available on HeinOnline from volume 1.
ScotusBlog: This page list petitions pending before the U.S. Supreme Court. Many, but not all, are circuit splits.
Westlaw
Try a boolean search using the strategy split conflict disgree! /s circuit authority and da(aft 2012). You should search in U.S. Court of Appeals cases and limit by date and filter as you see appropriate.
Another approach is to search for cases of novel cases or cases of first impression. A possible search strategy would be co(supreme court) & “first impression” & da(aft 2012). This search is possible at the state level as well.
Preview of United States Supreme Court Cases
This is an ABA publication available on HeinOnline. It covers cases that have applied for certiorari to the United States Supreme Court.
Lexis Advance
After selecting cases, then all U.S. Court of Appeasl, try a boolean search using the strategy split or conflict or disgree! /s circuit or authority . Use the timeline feature to refine your search.
For cases of first impression, select the jurisdiction and then try "first impression" or novel or new or original /s issue as your search strategy.