27. Except for a just and reasonable cause, no optometrist may refuse or cease to act on behalf of a patient. The following causes, among others, are considered just and reasonable:(1) absence or loss of the patient’s trust;
(2) the fact that the optometrist is in a conflict of interest or in a context such that his professional independence could be called into question;
(3) incitement by the patient to perform illegal, unjust or fraudulent acts.