Historian and former cop James Bultema knows about policing in America. He is the author of the acclaimed books, Guardians of Angels: A History of the Los Angeles Police Department and The Protectors: A Photographic History of Police Departments in the United States. Current LAPD Chief of Police Charlie Beck and former New York City Police Commissioner William Bratton thought so much of what Bultema had accomplished that they each wrote a foreword for these histories. For his new book, Unsolved: Cold-Case Homicides of Law Enforcement Officers, Bultema has compiled the first comprehensive national list of unsolved cases, including information on each fallen officer and, in many cases, an informed account of the officer’s murder. Unsolved is a touching tribute to these courageous law enforcement officers. Bultema is retired from the Los Angeles Police Department and lives in Arizona with his wife of 46 years.