Google Scholar includes Federal and State legal opinions

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Which court opinions do you include?

Currently, Google Scholar allows you to search and read opinions for US state appellate and supreme court cases since 1950, US federal district, appellate, tax and bankruptcy courts since 1923 and US Supreme Court cases since 1791 (please check back periodically for updates to coverage information). In addition, it includes citations for cases cited by indexed opinions or journal articles which allows you to find influential cases (usually older or international) which are not yet online or publicly available. Legal opinions in Google Scholar are provided for informational purposes only and should not be relied on as a substitute for legal advice from a licensed lawyer. Google does not warrant that the information is complete or accurate.

Google Blog: Finding the laws that govern us

As many of us recall from our civics lessons in school, the United States is a common law country. That means when judges issue opinions in legal cases, they often establish precedents that will guide the rulings of other judges in similar cases and jurisdictions. Over time, these legal opinions build, refine and clarify the laws that govern our land. For average citizens, however, it can be difficult to find or even read these landmark opinions. We think that's a problem: Laws that you don't know about, you can't follow — or make effective arguments to change.
Starting today, we're enabling people everywhere to find and read full text legal opinions from U.S. federal and state district, appellate and supreme courts using Google Scholar. You can find these opinions by searching for cases (like Planned Parenthood v. Casey), or by topics (like desegregation) or other queries that you are interested in. For example, go to Google Scholar, click on the "Legal opinions and journals" radio button, and try the query separate but equal. Your search results will include links to cases familiar to many of us in the U.S. such as Plessy v. Ferguson and Brown v. Board of Education, which explore the acceptablity of "separate but equal" facilities for citizens at two different points in the history of the U.S. But your results will also include opinions from cases that you might be less familiar with, but which have played an important role.
We think this addition to Google Scholar will empower the average citizen by helping everyone learn more about the laws that govern us all. To understand how an opinion has influenced other decisions, you can explore citing and related cases using the Cited by and Related articles links on search result pages. As you read an opinion, you can follow citations to the opinions to which it refers. You can also see how individual cases have been quoted or discussed in other opinions and in articles from law journals. Browse these by clicking on the "How Cited" link next to the case title. See, for example, the frequent citations for Roe v. Wade, for Miranda v. Arizona (the source of the famous Miranda warning) or for Terry v. Ohio (a case which helped to establish acceptable grounds for an investigative stop by a police officer).