a. wilfully disobey any lawful and reasonable orders;
b. are guilty of misconduct;
c. are guilty of fraud or dishonesty; or
d. are habitually neglectful in their duties.
It should be noted that taking part in a strike may not be a lawful reason for summary dismissal by the employers.
NOTE: Summary dismissal is a serious disciplinary action. It only applies to cases in which employees have committed very serious misconduct or have failed to improve themselves after an employer’s repeated warnings.
Example of employees' serious misconduct or dishonesty can be found in a High Court case (Chan Kan Ip Philip v Kone Elevators International ( China ) Limited). In this case, a company manager had made wrongful claim to recover personal entertainment expenses as company expenses. The Court ruled that such dishonesty could justify summary dismissal.
If you have evidence to justify that your sales executive has sent client information to a rival company (which can be considered as misconduct or dishonesty), then you can summarily dismiss him without giving him advance notice or wages in lieu of notice.