summarizing an article about criminal justice

summarizing this article;

 https://www.nytimes.com/2017/11/09/upshot/the-unsung-role-that-ordinary-citizens-played-in-the-great-crime-decline.html?rref=collection%2Ftimestopic%2FCrime%20and%20Criminals&action=click&contentCollection=timestopics&region=stream&module=stream_unit&version=latest&contentPlacement=1&pgtype=collection

summarize into one page only.