In criminal law, the decisive question is whether a so-called guarantor position exists. It arises from three sources: from the danger community itself, from prior conduct that creates the danger (ingerenz) and from the express or implicit takeover of duties. In mountain sports, the third source, the takeover of the leadership role, is the most important in practice. The Innsbruck doctoral dissertation by Barbara Rainer (2017) systematises the underlying framework, following the line drawn by Stabentheiner in JBl 2000, 273.
Six indicators for an implicit takeover. Stabentheiner and the Innsbruck dissertation derive six qualifying criteria from the Piz-Buin judgment, weighted as a "flexible system", not rigid subsumption but a holistic assessment. First, the personal responsibility of those being led as a starting point. Second, a hierarchy of subordination. Third, decision-making authority over route, gear, safeguarding, pace, breaks, abort. Fourth, special knowledge, climbing technique, route familiarity, relevant training. Fifth, "taking along" the weaker companion on a tour they would not have ventured alone. Sixth, trivialisation of recognisable dangers or asymmetric trust.
The OGH protective formula. In the 1998 Piz-Buin judgment, the OGH spelled out the protective rationale for the asymmetric setting: "The greater the differences in alpine ability and experience, the more intensively the weaker companion depends on the competence of the more experienced partner for a safe and gear-secured completion of the tour." If the led party "would not have ventured the tour without the more experienced one", the OGH’s wording, then a relationship of trust with heightened duties exists. Practical indicator: anyone who provides the gear, dominates route choice, leads from the front and makes decisions implicitly takes on the leadership role.
The Munich counter-test 2023. In the Munich case, a more experienced hiker did not bear "tour leader by courtesy" liability despite route planning and greater alpine experience, because her companion clearly communicated her limits at the summit, both decided jointly on route changes and the mountain rescue was called together. The constellation was shared decision-making, not unilateral takeover. "In most cases, every alpinist must first look after themselves", the Munich court’s phrase carries cross-jurisdictionally in Austria too.
Ingerenz, duties from danger-creating prior conduct. The second source of guarantor liability is rarer in mountain sports but should not be ignored. Anyone who creates a source of danger or lets it persist, triggering an avalanche and not warning others on the slope, or loosening a climbing belay and not correcting it, assumes a protective duty from that prior conduct. The Innsbruck dissertation cites the Rummel commentary: "Anyone who, even lawfully, creates a source of danger or lets it persist must take care that no harm results."
Protective formula for the tour. Anyone taken along on a tour should articulate clearly before the ascent what they can do and what they cannot, and who carries responsibility. Anyone taking a less-experienced partner along should make clear that this is a joint tour and not a guided one. These clarifications prevent both criminal liability and later disputes about who was responsible for what.