'The victims are blanked out'

DW: Dr. Egg, the prosecutors' office in Düsseldorf says the co-pilot was working despite being sick. Does this surprise you?

Rudolf Egg: If this is true, I'm not surprised. It would fit the picture of a person who's struggling with a deep mental crisis and ends up committing suicide.

What clinical picture are we looking at when somebody not only kills himself but also 149 people at the same time?

There certainly is no uniform picture for this, and you can't really do a psychological autopsy afterwards because the only things you have are clues and speculation. You can try to compare it with other cases in which the casualty figure is most likely far lower but the mental setup might have been similar.

Take deliberate wrong-way drivers on motorways for instance. These are depressed people with severe mental issues who don't care any more what's happening around them. The world and existing values don't matter to them while they're doing this.

Isn't that like somebody who's running amok?

I don't think that's the same. Somebody who's running amok feels hatred towards his murdered victims and in the final minutes might even feel elated over the deaths. I don't think this applies here. It's more about locking out reality and focusing on just one thing: my life, my world is pointless, I'm leaving now. And all the victims are blanked out.

This sounds like a spontaneous act rather than a planned one?

It could be a combination of the two. Many suicides are preceded by a longer period of hope, doubt and ultimately despair. Of course thoughts on how and when it could be done play a role in such a context. The final decision to actually act could however be spontaneous again and owed to a seemingly good opportunity.

And this could have played a role with the co-pilot. "I'm alone in the cockpit now and I can lock the door. Now nobody can stop me any more."

Is it at all possible to prevent something like this at the last minute?

The new rule that two persons must be in the cockpit at all times is wise. But if somebody really wants to commit suicide he or she will probably find a way to do so. Which is why this must be analyzed very thoroughly now. I'm concerned we might see a so-called Werther effect (a spate of copycat suicides - ed.).

Unfortunately, debating suicide and prevention can be rather distressing to people who are currently in such a crisis situation or have experienced one. It might even amplify their perceived threat and fear level. It could even drive them to actually commit suicide.

Does this effect also apply to extended suicide? There are websites where people who run amok are glorified. Can this persuade potential suicide candidates to follow suit?

This could happen. There is empirical data that rather convincingly proves there is copycat behavior in school shootings. But the suspected suicide killer in the Germanwings plane would probably fall into a different category.

School shooters hate their classmates and teachers. I don't think the co-pilot would have acted out of hate towards the passengers.

Do you think we'll be able to shed more light on his possible motives?

I think so. If it's confirmed that he underwent psychiatric treatment, there must be medical file. That would need to be opened and analyzed. I think the victims' families and friends have a right to this. They want to know what might have induced this man to drag their son, daughter or friend to their death with him.

Psychologist Prof. Dr. Rudolf Egg headed Germany's Center for Criminology in Wiesbaden until 2014.