Inspector Mark Hawthorne is a 28 year veteran of the San Francisco Police Department. He has been assigned patrol, field operations and investigations.  His current assignment is Crime Scene Investigations.  As a POST instructor he specializes in Instructor Development, Preliminary Investigations and Crime Scenes.  As a an adjunct faculty member of the City College of San Francisco Administration of Justice and Fire Science Department he acts as an advisor to the Forensic Science Club. Inspector Mark Hawthorne is the author of First Unit Responder: A Guide for Physical Evidence Collection for Patrol Officers and Fingerprints: Analysis and Understanding.

According to the book description of First Unit Responder: A Guide for Physical Evidence Collection for Patrol Officers, “Physical evidence cannot be wrong; it cannot perjure itself; it cannot be wholly absent. Only its interpretation can err. Only human failure to find it, study and understand it, can diminish its value." -Presiding Judge, Harris v U.S., 331 U.S. 145 (1947) HOW TO MAINTAIN THE INTEGRITY OF THE CRIME SCENE WHILE CONDUCTING AN INVESTIGATION.  First Unit Responder: A Guide to Physical Evidence Collection for Patrol Officers is a training guide and reference for patrol officers and criminal investigators, who conduct preliminary investigations of crime scenes, to aid in identification, collection, and booking of physical evidence. Written by a veteran of 24 years of law enforcement, the book stresses the importance of understanding the critical nature of physical evidence and preservation of the crime scene as part of the case against a criminal defendant. This book is an important tool for police academies that train recruits and veteran patrol officers, as well as for students of criminal justice who seek guidelines for proper collection and handling of physical evidence”