Borderline scenarios of outranking classification based on α-cut variation in fuzzy intervals: Application in police investigations

•New method for classifying actions called α-FlowSort.•Uses sections of the fuzzy interval to allow vertical and horizontal decision strategies.•Fuzzy sets with α-cut variation techniques.•Identification of outranking relations between fuzzy numbers.•Context of distributing resources to support criminal investigations.•Simulations and comparisons between the methods using a thousand random alternatives.