What can you do if an employee is harassing their colleagues?
An employee whose behavior is not acceptable and has a negative impact on the work environment is the employer's responsibility to deal with. The employer must address the problem, otherwise it can lead to serious work environment problems both for the employee and for the whole group.
It is of course good if you start by talking to the person in question, if possible. It is good if they hear the criticism and have a chance to explain themselves and make amends.
If talking to the colleague doesn't work, and if you have a safety representative or trade union representative at your workplace, contact them and tell them what the situation is. Their position of trust makes it easier for them to raise problems with the employer. The safety representative has considerable powers to demand that the employer takes measures to improve the working environment.
You have already spoken to your colleague's manager, and if he or she does not listen or understand, you should go higher up the hierarchy. The ultimate responsibility for health and safety lies with the CEO if it is a private sector company, the DG if it is a government agency, and the committee, board or council if it is a municipality or region. When presenting your case, distinguish between the case and the person. Try to be very specific about what their behavior means for the business and for your work environment. Focus on behavior and work results, for example, "I cannot prepare my documents on time, because I am waiting for materials from this person that they are not delivering".
The employer is then responsible for raising the issue with the colleague, finding out the cause and seeing what solutions are available. Sometimes the help of occupational health services is needed. It may also be a matter of reducing the workload or giving the person other tasks. The employer can also impose a disciplinary sanction, such as a written warning. Another possibility is that the person is reassigned to another position. The ultimate measure is dismissal for lack of cooperation, but in this case the employer must have made a real effort to investigate the problems and provided support, coaching, work adaptation, possible rehabilitation and explored redeployment possibilities.