DW: What's the right way for someone to help when they see a confrontation?

Kai Jonas: There's no rule of thumb for situations like these. Physical or violent intervention is often unnecessary. The ability to assess conflict situations requires a degree of experience or knowledge of human nature, which you can acquire through training. Preparation like that can help avoid the extreme risks that intervention can, unfortunately, sometimes entail - as it did in Tugce's case.

So how exactly can I intervene?

If possible, you should look for allies with whom to act in concert. Then you can share the various roles: One person talks to and protects the victim, another calls the police. Later on you all meet together. Of course, that's a kind of ideal situation that often isn't possible in reality. I absolutely do not mean to belittle or retrospectively criticize Tugce's actions and her intervention. What she did was extraordinarily brave.

Do I turn to the aggressor or the victim to defuse the situation?

Ideally, you don't focus on the aggressor but on the victim. If you focus on the perpetrator or perpetrators, which is something men often do, you very quickly end up in a spiral of escalation. It can then be very difficult to gauge where this spiral is going to end. It makes much more sense to focus on the victim and intervene in a way that pushes the conflict into the background. We call this paradoxical intervention. The aim is to protect the victim, get them out of the threatening situation and into a safe space. You should behave as if the violent situation doesn't exist.

So you should completely ignore the aggressor? What might such an intervention look like?

I could say to the victim, "Oh, we haven't seen each other for ages! Let's go and get a coffee." Then you use "gentle force" to drag the person with into a café, making clear to them: We're doing this to get you out of this dangerous situation. Of course, you don't actually have to have coffee with me.

That would be one way of completely negating the conflict, behaving as if I hadn't even noticed it. I might also just sit down next to the victim in the bus or on the subway and start up a conversation, as a kind of barricade. That way I create an additional barrier for the aggressor without actually criticizing their behavior and saying, "What you're doing is not okay."

Won't the victim be confused and feel even more cornered by people on two sides?

The victim is often trapped in the aggressor's magnetic field and isn't able to consider possible courses of action or spot possible ways to escape. That's why it's important to present the situation to the victim in such a way that they know exactly what they have to do: Go with me and get out of the situation. Victims are often paralyzed and don't know what they need to do.

But you need a very confident and firm manner to do this, which not everyone has.

You don't always have to intervene in these situations. Sometimes it isn't possible, and you don't dare - and sometimes not intervening is the better solution. But what you need to do then is be a good witness, call the police, get other people involved. That can be civil courage, too, because you're making clear that we're watching what's going on here. You don't have to be some kind of social Rambo; you don't have to intervene. People should act according to their own capabilities.

How do I know what I can expect of myself, in what situations, and in what way?

You can learn civil courage, but civil courage is also a lifelong learning process. No one's going to be able to intervene in every situation after a one-day training session. You can practice in the family or in your circle of friends. There are plenty of occasions where you can intervene there in a way that demonstrates civil courage. When people make racist or sexist comments, for example. You don't have to get into a fistfight. Civil courage has to be tailored to the environment of the person who takes the action. Everyone can set their own priorities and say: in situations like these I want to be vigilant.

Kai Jonas is a social psychologist at the University of Amsterdam.