P was a market research company that engaged part time interviewers to carry out research. The interviewers were under no obligation to accept work when offered it, were free to work for other companies, could complete the work any time they liked within a certain period, were paid a lump sum for the particular job, and were given an instruction booklet on how to interview, as well as detailed instructions for each job. The court held that the interviewers were employees.
Cooke J: The test is: “Is the person who has engaged himself to perform these services performing them as a person in business on his own account?" If the answer to that question is "yes," then the contract is a contract for services. If the answer is "no," then the contract is a contract of service.” No exhaustive list of factors that show whether this is the case. Control is important but not of itself decisive. Important factors might be whether the labourer “his own equipment, whether he hires his own helpers, what degree of financial risk he takes, what degree of responsibility for investment and management he has, and whether and how far he has an opportunity of profiting from sound management in the performance of his task.” Here, the instruction booklet (‘Interviewer’s guide’) was incorporated into the terms of the contract and demonstrated a high degree of control.