CAT/C/SVK/CO/3 (b) Ensure that the Istanbul Protocol is made an essential part of training for all medical professionals and other public officials involved in work with persons deprived of their liberty; (c) Ensure instruction and methodical guidance for police on the need to respect the principles of necessity and proportionality during police interventions, as well as on the absolute prohibition of torture and other State obligations under the Convention. Data collection 19. The Committee regrets the absence of comprehensive statistical data, disaggregated by age, gender and ethnic or national origin, on complaints, investigations, prosecutions and convictions in cases of torture and ill-treatment by law enforcement and prison personnel, or on trafficking and domestic and sexual violence, including means of redress. The State party should compile statistical data relevant to the monitoring of the implementation of the Convention at the national level, including statistics, disaggregated by age, gender and ethnic or national origin, on complaints, investigations, prosecutions and convictions in cases of torture and ill-treatment, trafficking and domestic and sexual violence, and on means of redress, including compensation and rehabilitation, provided to the victims. Follow-up procedure 20. The Committee requests the State party to provide, by 14 August 2016, follow-up information in response to the Committee’s recommendations relating to the following: ensuring fundamental legal safeguards; carrying out investigations into allegations of the excessive use of force; providing data on such investigations; and publicly stating a policy of zero tolerance of the excessive use of force, as contained in paragraphs 8, 11 (a), 11 (b) and 11 (g), respectively, of the present document. Other issues 21. The Committee invites the State party to consider ratifying the United Nations human rights treaties to which it is not yet party, namely, the Optional Protocol to the Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment and the International Convention on the Protection of the Rights of All Migrant Workers and Members of Their Families. 22. The State party is requested to disseminate widely the report submitted to the Committee and the present concluding observations in appropriate languages through official websites, the media and non-governmental organizations. 23. The State party is invited to submit its next report, which will be the fourth periodic report, by 14 August 2019. For that purpose, the Committee will, in due course, transmit to the State party a list of issues prior to reporting, considering that the State party has accepted to report to the Committee under the optional reporting procedure. 8