Experts have warned the Public Health Ministry's proposal to criminalise possession of more than one methamphetamine pill as possession with intent to sell rather than for personal use could have serious consequences.
Public Health Minister Anutin Charnvirakul maintains the amendment will be effective as a legal measure to deter people, especially the young, from becoming involved in illegal drugs.
At present, those found with 15 or fewer pills in their possession are regarded as having them for personal use only and are subject to rehabilitation, according to Deputy Public Health Minister Sathit Pitutecha.
Mr Sathit said that authorities should analyse suspects' circumstances before labelling them dealers by law.
According to the proposal, anyone in possession of two meth pills, who shares one of them with a friend, for example, will be legally considered to be dealing drugs.
Mr Sathit said the problem should be addressed in collaboration with families and communities, and changes in the law should be considered, so the issue can be tackled effectively.
"If we look at it from a legal standpoint, tougher laws and harsher punishment may lead to a similar situation that occurred during the Thaksin Shinawatra government," he said.
Although the policy may have reduced the illicit drug trade, it was criticised for giving law enforcement officers excessive power and leading to the deaths of many innocent people in the process.
"However, in the long run, that violence failed to offer a solution to illegal drug use," Mr Sathit added.
Wayo Assawarungruang, a list MP of the Move Forward Party (MFP), said the underlying logic behind a tougher approach is problematic as it assumes guilt prior to a fair trial.
This "assumption by law" is not an effective tool for drug suppression since it has the tendency to hinder rather than assist drug suppression work, said Dr Wayo, citing research and statistics regarding this topic.
He added that if the amendment is adopted, more people will be jailed, and prisons will become even more crammed.
Dr Wayo said prison overcrowding is a persistent problem globally and has been cited as a human rights concern in Thailand.
Justice Minister Somsak Thepsutin countered the new law would allow for addicts who pose a threat to medical staff and the public to be detained in a more timely fashion.
Mr Anutin had said the proposal had not yet been formally put before the cabinet at its weekly meeting and was pending additional input from drug rehabilitation agencies.
In response to criticism the amendment might lead to corrupt police planting illegal drugs on victims, the public health minister said he was more concerned about the need to keep families and members of the public safe from drug addicts and traders.