They were walking around with their notebooks taking note of what they had seen. So here you had officers who were previously almost illiterate, for whom basically stopping a car in the correct way was a major accomplishment, now reproducing a crime scene in a fairly sophisticated fashion, gathering evidence and taking notes.
Il n'y a pas si longtemps, nous avions des agents pratiquement illettrés, pour qui l'interception adéquate d'un véhicule représentait un exploit, alors qu'aujourd'hui, ils reproduisent une scène de crime sophistiquée en recueillant des preuves et des notes.