HeinOnline shows statistics about individual articles and authors.
In search results in the Law Journal Library, when you select an article you see a pop-up with statistics for that article. For example, in the search results below (from July 1, 2016), choosing Kathryn A. Watts, Proposing a Place for Politics in Arbitrary and Capricious Review, 119 Yale L.J. 2 (2009), shows that it has been cited by 119 articles. Choosing the next article in the list, Kathryn A. Watts & Rafael I. Pardo, The Structural Exceptionalism of Bankruptcy Administration, 60 UCLA L. Rev. 384 (2012) shows it was cited by 23 articles. The total citations to an author are shown after his or her name (for instance, 241 for Prof. Watts and 202 for Prof. Pardo).
Clicking on the link (e.g., "Cited by 119 Articles"), takes you to a list of those articles, with statistics about those articles and their authors. ScholarCheck very quickly give you an entry to the web of scholarship.
Note that the display includes the search that HeinOnline uses to generate the list—("119 Yale L.J. 2" OR "119 Yale L. J. 2" OR "119 Yale Law Journal 2") in Law Journal Library—so you know exactly what was searched.
For each author in its database, HeinOnline creates a profile, listing all the author's papers along with ScholarCheck metrics (e.g., cited by articles, cited by cases, cited in past 1-2 years). To find an author profile, search the Law Journal database for that author's name, then click on the name in any of the results.
Authors can add to their profiles. For instance Prof. Clark Lombardi's profile includes his photograph, a link to his UW Law profile, and a brief biography. The articles listed in Prof. Lombardi's profile include works he has published under slightly different names (Clark Lombardi, Clark B. Lombardi, and Clark Benner Lombardi). It's a good idea for authors to let Hein know about name variants so all the works (and statistics) are pulled together. UW Law authors: if you would like help with your HeinOnline profile, ask reference.
HeinOnline's database is very large—including many foreign journals as well as almost all U.S. law reviews (going back to their inception!)—but it does not include non-law journals, treatises, and many other works that could cite a legal article.