Adders LLP is a limited liability partnership, registered in Ontario, practicing as chartered accountants. It has 15 partners and over 200 employees. One of its major clients, Norne Inc., is a small but dynamic resource company, incorporated in Ontario.
Until about two years ago, the Norne account was handled directly by Counter, a senior partner. More recently, the account has been handled by Turner, a young accountant who is considered to be in line for a partnership. Turner currently reports directly to Counter. Although Counter has continued to exercise supervision, discussing the account with Turner from time to time, Turner has been increasingly left to work by herself.
In preparing the corporate returns for the last two years, Turner made numerous errors including failing to advise Norne of the availability of enormous research and development tax credits. Additionally, a Canada Revenue Agency audit discovered other significant errors resulting in huge penalties and significant interest claims.

Adders LLP is now being sued by Norne for the losses it suffered as a result of the errors in filing the returns.

Briefly consider the liability of (a) Adders LLP, (b) Counter, and (c) the other partners in the firm.