In elevator journey prioritization often calls for larger groups are prioritized. This is often misused by placing elevator calls for larger groups that are actually travelling. This problem can be reduced by identifying the calling person when placing the call and again in the elevator. The number of people in the elevator can be estimated by using machine vision or weight-based approximation methods. When the number of passengers is not known the possible misuse can be suspected if a person places considerably more group calls as than average.