After completing the research project for his Doctorate, John joined the International Tin Research Institute where he carried out research into tin oxide based gas sensors.

In 1987, John joined Johnson Matthey plc where he worked as a Development Chemist, developing new supported metal catalysts for industrial processes as well as providing technical support to production staff in the manufacture of catalysts. This work included overseeing the production of trial batches of new catalysts.

John joined Hawkins in 1989 and was trained to carry out the forensic investigation of fires and explosions. Since then John has carried out over 1000 investigations, the majority of which have involved fires and explosions, although he also uses his knowledge of chemistry to investigate other problems/incidents, such as cases involving fireworks, explosives and poisoning.

John has also carried out a number of personal injury investigations primarily in handling and lifting accidents and guarding of work machinery.

John has a range of experience involving the legal process and has given evidence in the capacity of an expert in both Civil and Criminal Courts on several occasions. He is listed as an expert in the Expert Witness Directory.

John is currently an Associate Director and is the Regional Manager of the Bristol office.