how did information historians get from newspapers by different from that found in police reports
Answers
The nature of information that the historians get from old newspapers and police reports can be entirely different. Typically, a historian would collect information from a wide variety of sources that includes both official and unofficial documents. The police report comes from an administrative viewpoint and the types of details that we can obtain from them are often restricted.
A police report is strictly confined to the procedures and is concerned with record-keeping, rather than building a narrative. Journalism and reporting tools follow a different approach that might bring out the finer details about an event or a happening. Often police reports might oversee or neglect information that does not directly serve the function of law enforcement.
Being a mass media, newspapers provide more backdrop, context and elaborate descriptions. But the relative merits and accuracy of a piece of information from any source, can only be determined after proper research and investigation. For getting a balanced and clearer picture of a period in history, historians often go through as many sources as possible, while keeping in mind the biases and interests that could be behind them.