While it is hoped that employee terminations are without incident, terminated employees sometimes become belligerent or obstinate when they are told they are being let go. If it becomes necessary, yes, an employer can call the police if a terminated employee will not leave the premises.
However, there may be other options that should be tried first. It is best not to get into an argument with the terminated employee but to make sure that the person handling the situation can keep their cool. The reason the employee refuses to leave should be identified. Maybe it is something that can be addressed—maybe not. The employer should assess the situation before calling the police to see if it can otherwise be resolved.
It may be sufficient to have someone escort the terminated employee off the premises. If he or she will not leave with an escort, then the employer may call building security personnel to escort the employee off the premises. If the building does not have security personnel, or the building’s security personnel are unable to handle the employee, or the employee simply will not leave despite efforts to reason with the employee, then the employer should call the police. It is generally not prudent to allow a terminated employee to remain on the premises once an exit interview has been completed and their personal belongings are collected.
Of course, if the terminated employee threatens violence against any persons, threatens to destroy company property, or engages in any violent or destructive behavior, the employer should call the police immediately.