The case against Anis Amri, the suspect in Monday's attack, has some doubting the competency of Germany's security services. Those who do would be well served to remember that Germany has been spared the most severe terrorist attacks. Earlier this year, the Federal Criminal Police Office (BKA) released a list of 11 thwarted attacks. This includes the 2007 Sauerland terror cell, which plotted bombings of high-profile targets around Germany. The cell's members are now serving long prison sentences.

True, luck has played a role. The Cologne suitcase bombers, for example, failed to blow up trains in 2006 due to faulty explosives. The summertime arrest of Jaber al-Bakr, a Syrian refugee accused of planning an attack in Chemnitz, can be marked a success, despite mistakes made in the course of the investigation.

Arrests require evidence

Security services are going on this assumption as well with the Tunisian-born Anis Amri, whose asylum request had been denied. Six months of observation concluded he posed no danger to the state. The investigation was therefore ended, but how long it was conducted for shows it was anything but casually handled. In light of the Berlin attack, it is of course tragic Amri could not be arrested due to lack of evidence, but no one can be detained or convicted without it.

That value stands at the core of rule of law and must be adhered to without exception. Any deviation would be an additional victory for terrorism over freedom and human dignity. Terrorists, at least for now, have succeeded in instilling fear in open society. Germany should not do these perverse, hate-filled criminals the favor of labelling their own security services as a security risk. Mistakes must be recognized and rectified, however blanket criticism is irresponsible and populist.

State of emergency

How else should Anis Amri have been stopped from carrying out his alleged attack? Open-ended detention without charge would put Germany into a state of emergency such as the one France has been under since the attacks in Paris in 2015. The deadly truck attack in Nice happened anyway - clearly, a macabre model for Monday's Christmas market attack in Berlin.

Unfortunately, such attacks can be expected anytime. Security services count the number of threats in the hundreds. It would be impossible to monitor them all around the clock, and only the highest profile ones can be. It may sound paradoxical given the tense mood at the moment, but Anis Amri is a good example of effective policing.

Not enough evidence

Amri had been on the radar. As far as we know, his disappearance was not the result of failure, but lack of evidence. Only if the current investigation reveals otherwise can we then question the competency of Germany's security services.

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