Key paragraph(s) can be found below the document.CASE-of-HENTSCHEL-and-STARK-v-GERMANY-by-EGMR
91. The Court reiterates that where the competent national authorities deploy masked police officers to maintain law and order or to make an arrest, those officers should be required to visibly display some distinctive insignia, such as a warrant number. The display of such insignia would ensure their anonymity, while enabling their identification and questioning in the event of challenges to the manner in which the operation was conducted […]. The consequent inability of eyewitnesses and victims to identify officers alleged to have committed ill-treatment can lead to virtual impunity for a certain category of police officers […].