Philippines mayor Antonio Halili shot dead by sniper, police chief says
https://edition-m.cnn.com/2018/07/01/asia/philippines-mayor-halili-tanuan-shot-intl/index.html
Zero-tolerance policy is not good in terms of various reasons.
First, it causes fatal judgement on innocent people who are mistakenly arrested.
If they are sentenced to death, it's horrible.
Second, without preparing for alternative job for drug traffickers, they would lose job, and then starve to death or rush to other crimes.
Third, relatives of those people would hate leaders radically, and try to kill them in some cases like this incident.