geneva unite nations human right boss call mexico senate tuesday adopt propose law internal security say would enshrine role military law enforcement time strong police force need zeid ra ad al-hussein u.n. high commissioner human right say decade arm force deploy war drug violence abate extrajudicial kill torture disappearances continue commit various state non-state actors statement recognize mexico huge security challenge violence sow powerful organize crime group zeid say adopt new legal framework regulate operations arm force internal security answer current draft law risk weaken incentives civilian authorities fully assume law enforcement roles u.n. right boss urge mexico enshrine army 's role