Previous research on left-wing extremism in Germany relied largely on measurements that are unsuitable to track down extreme attitudes. In the absence of a clearly defined item battery of left-wing extremism researchers based their predictions largely on indicators like voting behavior or the left-right self-placement scale. Building on a large-scale investigation of data from the past 20 years the paper shows however, that such items do not serve as adequate proxies, since those labeled as “extreme” do not hold extreme attitudes in most cases. Hence, potential for extremism on the political left is either over- or underestimated, depending on the respective attitude. Analyzing a variety of left-wing extreme attitudes across the past two decades shows that there is indeed a core of those attitudes that seems to resemble what we would call a traditional left-wing extremist identity. The paper subsequently suggests an item battery that can serve as a starting point for further developing an index of left-wing extremism. Finally the potential of the extreme left is assessed using the constructed index. The results show that the estimated potential differs substantially from conventional measurements not in quantity but in its composition. As a result, traditional measurements fail to predict actual left-wing extremism. Especially anti-pluralist mindsets are heavily neglected. Implications are thus discussed for Germany and on a greater perspective.
