blue lie noun2 •A lie told to protect the reputation of one's group or organization.About Manete's evidence, that Francis had asked him why he did not join the people, why he did not fight, Francis said, "No, he is telling a blue lie." — 1990 •A lie told by a police officer in order to get someone to comply with his or her wishes, thereby avoiding the use of force.Blue lies are different from police placebos in that they are not told to help or comfort the person lied to but, rather, to exert control — 1984 formsblue lies