Weight
The schedule to the Drug Misuse and Trafficking Act sets out 5 categories of weight (or quantity) for each prohibited drug and plant: small quantity, traffickable quantity, indictable quantity, commercial quantity and large commercial quantity.
The weight or quantity determines the category of offence and the maximum penalty (which influences the severity of the actual penalty imposed in a particular case). The weight or quantity also determines whether the case is heard as a summary matter before a magistrate in the Local Court (the great majority of drug offences are dealt with summarily), or as an indictable matter before a judge and jury in the District Court. Determining the jurisdiction (ie Local Court or District Court) is covered by both the Drug Misuse and Trafficking Act (sections 30 and 31) and by the Criminal Procedure Act, 1986.
In many cases, the prosecution (and sometimes the accused) can determine that a case is to be heard in the Local Court even though it could be heard in the District Court by a judge and jury. Somewhat confusingly, "indictable" matters_ including charges concerning indictable quantities of prohibited drugs - are frequently heard summarily.
The maximum penalty that can be imposed by a Local Court is a fine of $110,000 and two year's jail (three years jail if sentencing for more than one offence), regardless of the maximum penalty set out in the Drug Misuse and Trafficking Act (see sections 27 and 28 Criminal Procedure Act 1986).
The purity of the drug does not matter_ only the weight (section 4). Under the Drug Misuse and Trafficking Act, one gram of a powder that is 10 percent heroin and 90 percent glucose is treated as one gram of pure heroin. [BT: my emphasis added]
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Ongoing dealing
There is a special offence of supplying drugs on an ongoing basis(section 25A). The offence involves the supply of a prohibited drug (except cannabis) on three separate occasions within a 30 day period. The acts of supply must be for some financial or other material reward. It does not have to be supply of the same drug.
A charge of ongoing dealing is usually laid where an undercover police officer buys drugs from the same street dealer on three different days. The police are not obliged to arrest the dealer immediately after the first sale.
The maximum penalty for this offence is a $385,000 fine and 20 years jail, regardless of the weight of the drug supplied, or the value of the transactions (section 25A(1)). This is equivalent to the maximum penalty for the supply of a 'commercial quantity' of drugs. A person convicted of an offence under this section is not eligible to be dealt with by the Drug Court.
Large scale supply and cultivation
Higher penalties apply for charges involving the supply of larger amounts of drugs. The Drug Misuse and Trafficking Act divides trafficking offences into a number of categories: 'indictable', 'commercial' and 'large commercial' quantities. Proof of possession of the relevant quantity is sufficient to establish that a person is guilty of that particular trafficking offence, unless the person can prove they were in possession for reasons other than supply, which is logically more difficult to do the greater the quantity of drugs involved.
The maximum penalty for dealing with an 'indictable' quantity of a drug is a $220,000 fine and 15 years imprisonment (10 years for cannabis) _section 32. For a quantity of drugs in the 'commercial' range, the maximum penalty is a $385,000 fine and 20 years jail (15 years for cannabis) _ section 33(2). For the 'large commercial' quantity, fines of $550,000 and life imprisonment (20 years for cannabis) can be imposed _ section 33(3).
