The National Legislative Assembly has endorsed a bill setting standard requirements for companies providing security services and for qualifications to obtain a permit to work as a security guard.
The assembly passed the bill in the final reading by a vote of 175-172 with four abstentions.
The law will take effect 120 days after being promulgated in the Royal Gazette.
Under the legislation, a company offering security guard services must obtain an operating licence valid for four years, and which can be renewed.
A security guard must have completed Mathayom 3 (Grade 9) education or higher, be aged at least 18, and hold Thai nationality. They are required to obtain a licence to work which will be valid for three years, and only extendable after an assessment of past performance.
The law prohibits convicted sex offenders from working as security guards.
The law springs from an incident in September last year involving former security guard Chatree Seedee, 27. He was accused of killing a four-year-old girl, then stuffing her body in a black plastic bag which he left in a drain near an apartment where he had worked as a security guard in the Bukkhalo area of Bangkok.
Police later found Chatree was a Myanmar national.
The incident prompted calls from the public for better regulations to screen security guards.
For those convicted of criminal offences including murder, physical assault, stealing, gambling and drugs, they can apply for a licence three years after completing their sentences.
The legislation also sets up a committee to oversee the security guard business, chaired by the national police chief. All security guards must pass a security course at training centres approved by the committee before receiving a licence.
Owners of security guard businesses can be sentenced to one year in jail and a fine of 20,000 baht if they operate without a licence, and six months in jail and a fine of 10,000 baht if they employ unlicenced security guards.