Some of the most common drug offences are for possession, use and supply of prohibited drugs. Each drug offence has specific legal 'elements' which the prosecution must prove beyond reasonable doubt. In this section, we examine the necessary legal elements for the offence of possession. These elements are established by the terms of the legislation, as interpreted by precedent court decisions.

Possession of a prohibited drug is an offence under section 10 of the Drug Misuse and Trafficking Act 1985 (NSW). To prove possession, the prosecution must show beyond reasonable doubt that:

  • an illegal drug was in a person's 'custody' or 'control', and
  • the person knew that they had custody or control of a prohibited drug.

Proving custody or control

The police must prove that the person actually had control over drugs found, for example, in their car or house. The fact that a person owns a car, or owns or rents a house, does not necessarily mean that they own things in it. If a person knows that there are drugs in their house, but someone else has control of them (that is, the person does not own the drugs or have any right to use them), they are not guilty of possession.

What is custody or control?

Custody means immediate physical possession, such as a person having something in their pockets. Control refers to the right to do something with the drug - for example, to keep, consume or share it.

Momentary custody and control

A person can be found guilty even if their custody and control was only momentary: for example, by taking a joint passed to them.

Proving knowledge

The prosecution must prove that the person knew they had something in their physical custody and control that was, or was likely to be, a prohibited drug.

The legal test for the prosecution is not what a reasonable person might or should think in the circumstances. The actual knowledge of the accused person must be proved. Knowledge can be inferred from the circumstances in which the drugs were discovered.

If someone is apprehended with drugs on them, a court would probably reasonably infer that they had knowledge and control of those drugs. It is difficult for someone in this situation to escape the inference that they knew what was in their bag or sock or pockets. Similarly, where drugs are stored in a part of a house that is private (say, in a person's bedroom) it is open to be inferred that they had possession of those drugs.

The case of the leftover drugs

A guest at a party left marijuana in a bathroom cupboard. During a raid some time later, a resident of the house told police that he knew the drugs were there and that he had intended to dump them. He was found not guilty of possession because he had laid no claim to the drugs and had exercised no control over them. Knowledge that the drugs were there was not enough (Solway v R (1984) 11 A Crim R 449).

Shared houses

When drugs are found in a place that is accessible to a number of people (such as the living room of a shared house), it may not be inferred that any single person has possession of the drugs. The drugs could belong to anybody who had access to the room.

If no one makes a statement to the police that the drugs are theirs (or someone else's), it is likely that no-one will be convicted.

The case of the household drugs

A man lived with his girlfriend, his mother, his brother and another couple in a three bedroom house. The police found marijuana inside the lounge in the living area, a room to which all the occupants had regular access. The man's conviction was overturned on appeal. The Court of Criminal Appeal said that it was necessary to prove that he had the drugs in his exclusive physical control, and that this was difficult because of the large number of people having equally free access to the room in which they were found (Filippetti v R (1984) 13 A Crim R 335).

The prosecution must rule out all other reasonable explanations. If there is the possibility of several people having access to the drugs, there is room for reasonable doubt about whether the drugs are possessed by the accused. They could be possessed by someone else.

It is possible that all people living in a shared house could be charged and convicted of possession if the police can prove that they all had knowledge and control over (or access to) the drugs. But that would require evidence that all people had access - for example, statements from all the residents admitting they had knowledge and access.

Charges against several persons

If a number of people are charged with possession in this situation, the prosecution must prove in each case that the person charged had possession of the drugs.

This can be difficult. Courts are not allowed to presume that all the people must have shared possession - each individual accused is presumed innocent. Without admissions ('Yeah, I knew the weed was in the cupboard...'), it may be difficult to prove that any one of the accused is guilty of possession.

Medicinal cannabis

Cannabis used for medicinal reasons remains prohibited.

It is not a defence to a charge of possession of cannabis (or self-administration or cultivation of cannabis) that the person used the cannabis for a legitimate medical reason. However, evidence of a significant illness or medical condition can be a relevant issue to be taken into account in sentencing.

Many cannabis preparations designed for medicinal applications will have a higher proportion of cannabidinol (CBD) and less tetrahydrocannabinol (THC) than other cannabis. These preparations are still defined as ‘cannabis’ under the NSW law so it remains an offence to possess or supply or cultivate such products.

The NSW Government is conducting a trial of medicinal applications of cannabis for a range of conditions with the intention of considering legal reform when the results are known.

Terminal Illness Cannabis Scheme

People with terminal illnesses and their carers can register on the Terminal Illness Cannabis Scheme. The register is maintained by the NSW Police. The registration process requires a doctor to certify that the person has a terminal illness, which is defined to mean an illness which in reasonable medical judgement, in the normal course and in the absence of extraordinary measures, will likely result in the person’s death.

A person listed on the register or their carer will not be prosecuted for possession of up to 15 grams of cannabis or 2.5 grams of cannabis resin (hashish). Being on the register is not a defence to a charge of cultivation or supply or driving under the influence of a drug or driving with the presence of THC in saliva.

Synthetic drugs

‘Synthetic’ drugs are, or are at least marketed as, chemically different from but with similar effects to better known illicit drugs. The possession, manufacture, production or supply of ‘synthetic’ drugs is criminalised by a combination of the Poisons and Therapeutic Goods Act 1966and the Drugs Misuse and Trafficking Act 1985.

A number of synthetic drugs are listed by their market names on Schedule 9 of the Poisons Standard. The Poisons Standard is a list of poisons and other substances, gazetted by the Poisons Advisory Committee, whose members are appointed under the Poisons and Therapeutic Goods Act 1966. It is an offence under section 25B of the DMTA to possess, manufacture, produce or supply a substance listed on Schedule 9 of the Poisons Standard.


The maximum penalty for possession of a Schedule 9 substance is a $2200 fine or 12 months' imprisonment or both (section 25B(3)).

The maximum penalty for the manufacture, production or supply of a Schedule 9 substance is a $2200 fine or two years' imprisonment, or both (section 25 B(1) and (2) DMTA).

The maximum penalties are generally less than for comparable offences involving prohibited drugs. As there are no categories of offence based on quantity, the maximum penalty is the same whether the offence involves a substantial amount or a smaller amount.

‘Psychoactive substances’

In addition, Part 2C of the DMTA creates offences for dealings with ‘psychoactive substances’, which may include synthetic drugs not included on Schedule 9 of the Poisons Standard.

A psychoactive substance is defined (section 36ZD(1) DMTA) as a substance that, when ‘consumed’, has the capacity to induce a psychoactive effect. ‘Psychoactive effect’ is broadly defined (section 36ZD(1) DMTA) to include any stimulation or depression of the central nervous system, hallucination or significant disturbance or change to perception.

There is obviously room for considerable overlap between substances which are psychoactive substances and which are also prohibited drugs or otherwise controlled or criminalised by other legislation. Part 2C of the Act does not apply to a substance which is a prohibited drug or plant under the Drugs Misuse and Trafficking Act.

It is an offence to manufacture or supply a psychoactive substance for human consumption, either knowingly or recklessly in relation to the intended supply (section 36ZF DMTA). There is no offence of possession of a psychoactive substance.

It is an offence to publish or display any form of advertising which, knowingly or recklessly, promotes the consumption, sale or supply of a substance for its psychoactive effect, or provides information on how or where a psychoactive substance may be acquired (section 36ZG DMTA).

Again, as for Schedule 9 Poisons Standard substances, there are no categories of offence based on quantity.