Google Scholar is indexing the Law Journals in HeinOnline to make the more than 1,100 titles searchable in the Google Scholar interface. The indexing is still ongoing, as Google Scholar has not fully indexed all of the titles in the Law Journal Collection as of yet. Over the next 30 days or so they should near completion of the indexing at which point the entire HeinOnline Law Journal collection will be searchable in Google Scholar.
So how does it work? Go to Google Scholar and search for a Law Journal or an article name from within a Law Journal. If the article is available in HeinOnline, it will be included in your search results, like the example below.
When you click on the link to open the article in Google Scholar, you will see the HeinOnline logo on the right sidebar with a link that says "Subscribers Click Here To Access". When you click on the access link, you will be taken directly to that article in HeinOnline. NOTE: You may be asked to log in once you reach the HeinOnline site. If so, simply log in and then you’ll be directed to the article.
(from HeinOnline Weblog)