James Ward - who's known as Jim - is currently being treated at Frenchay Hospital in Bristol.
The 58-year-old was shot in the head at his office in Devizes on Monday 2nd June, at around 3pm and is said to be in a life threatening condition.
Police have arrested a 62-year-old man in connection with the incident and have been given more time to question him. It's thought the two men are known to each other.
A weapon, believed to be a shotgun has been recovered.
A police cordon around the Morris Goddard and Ward law firm is expected to remain in place until tomorrow afternoon while forensic teams carry out their investigations.
Police are still appealing for anyone who was in the area of St John's Street, around the time of the incident to contact Police on 101.
A mobile police unit will be set up in the Market Place so anyone with concerns regarding the incident can talk directly to local officers.
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