Loren W. Christensen began his law enforcement career in 1967 as a Military Policeman (Army). He joined the Portland (Oregon) Police Bureau in 1972, retiring in 1997. During his years on PPB, he worked street patrol, child abuse, dignitary protection, Intelligence, street gangs, and in the training unit. Christensen began training in the martial arts in 1965. Over the years he has earned a total of 11 black belts, eight in karate, two in jujitsu and one in arnis. As a professional writer since 1978, he has written 45 books, dozens of magazine articles, and edited a police newspaper for eight years. He has written about martial arts, missing children, street gangs, school shootings, workplace violence, police-involved shootings, nutrition, exercise, prostitution, and various street subcultures.

Loren was inducted into the martial arts Masters Hall of Fame in 2011. Loren W. Christensen resides near Portland Oregon.