Newspapers, law reviews, and legal journals are examples of secondary legal sources in U.S. law. Court cases and original court documents are considered primary documents. Newspapers can be a good source of information about a case that is still pending or about a particular suspect.
What is a docket? "A log containing the complete history of each case in the form of brief chronological entries summarizing the court proceedings." Each case has a unique docket number.
What are court filings? All the papers filed with the court. Examples might be pleadings, motions, briefs, affidavits, and exhibits.
Dockets and court filings are typically maintained by the clerk where the court case has jurisdiction. At times these records are available online, but it varies by state and typically there is a fee per page.
Source: Library of Congress, Dockets and Court Filings
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