Hawthorne Security was established in 1961 as a security guard provider by Mr. Robert Duncan in Kingston, Ontario.  The operation was sold in 1990 to Kingston resident Mr. Robin Brent.  In 2012 it was acquired by Marilyn MacKinnon. Prior to this acquisition, Marilyn MacKinnon had a 10-year management relationship with Hawthorne.  In February 2018 Russell Murphy, a licensed security guard & private investigator with Hawthorne, took over the Grey Bruce Owen Sound & surrounding areas & registered his company as Hawthorne Security & Investigations Inc.

Both companies are registered with the Ministry of Community Safety and Correctional Services.  All Hawthorne Security Guards are licensed with this ministry following a thorough police reference check to qualify each applicant.  Additionally, all guards are trained in First Aid and Smart Serve where applicable.