Johnston Montgomery Watson Barristers & Solicitors, Notaries Public, Lawyers Practicing in Association in Whitby, Ontario Welcome to Johnston Montgomery Watson, Barristers & Solicitors, composed of the law firms of Johnston Montgomery and Erin L. Watson, practicing in association. Our office has served clients from the Durham Region, GTA and Northumberland for almost 50 years in the areas of litigation, wills, trusts and estate administration, corporate and commercial matters, and real estate.