Mexican law presumes an accused person is guilty until proven innocent.
- As in most other countries, the purchase of controlled medication requires a doctor’s prescription.
- It's against Mexican law to take firearms or ammunition into the country (even unintentionally).
- A law passed in 2009 decriminalized the possession of small amounts of certain drugs for personal use – including marijuana (up to 5g), cocaine (500mg), heroin (50mg) and methamphetamine (40mg). The law states that first-time offenders do not face criminal prosecution. Selling drugs remains illegal, and people found in possession may still have to appear before a prosecutor to prove that the drugs are truly for personal use. The easiest way to stay out of trouble is to avoid drugs altogether.