Expert Evidence in Drug Trafficking
In considering whether to qualify an officer as an expert in drug related fields of expertise, the question is not whether the witness knows more than the average officer but rather whether there is expertise to explain the vagaries of drug trafficking milieu.
It is not relevant evidence to have an expert qualified in the customs of the drug trade to comment on his familiarity of the use of blind couriers on the issue of establishing the mens rea of trafficking. 
An expert is entitled to develop that expertise "by observations of the drug trade, by talking to other experts, and by general involvement in policing of the drug trade".
- R v N.O., 2009 ABCA 75 (CanLII)
- R v Sekhon, 2014 SCC 15 (CanLII)
R v Plourde, 2017 ABCA 367 (CanLII), at para 6 - ("An expert on drug activity is entitled to develop that expertise by observations of the drug trade, by talking to other experts, and by general involvement in policing of the drug trade.")
Example Areas of qualification
Courts have previously accepted the following area of expertise relating to drugs:
- relationship between couriers, overseers and contact persons in drug importation
- how drug traffickers work 
- drug trafficking transactions 
- intention to traffick 
- pricing and jargon 
- monetary value of hash and heroin 
- impairment by drug recognition expert evidence
- the how marijuana is grown, the stages of growth, activities surrounding a grow operation, the effect of moisture on the plants during harvest.
- significance of short notice bookings and cash payments as indicators of drug importation schemes.
- "the production, manner of use, packaging, distribution, prices, consumption patterns, paraphernalia, jargon, practices and habits of users, practices and habits of traffickers, and the observable effects of cocaine, methamphetamine and ecstasy." 
- "drug trafficking, drug hierarchies, the meaning of coded language, and police anti-detection techniques"
- R v Hui 1988, O.J. No. 1881 (ONCA) (*no CanLII links)
- R v Joyal, 1990 CanLII 3344 (QC CA)
- R v Ballony-Reeder, 2001 BCCA 293 (CanLII)
- R v Bryan, 2003 CanLII 24337 (ON C.A.)
R v Fougere (1988), 40 CCC (3d) 355 (NBCA)(*no CanLII links)
R v Somerville, 2012 NBCA 23 (CanLII)
- R v Mohammadi, 2006 QCCA 930 (CanLII)
- c.f. R v Thomas, 2012 BCPC 215 (CanLII)
R v Cripps, 2014 ONCJ 189 (CanLII)
- Somerville, supra
- R v Lewis 2012 ONCA 388 (CanLII)
R v Qureshi, 2011 ABPC 92 (CanLII) at para 22
R v N.O., 2009 ABCA 75 (CanLII),  AJ No 213
- R v Dritsas, 2012 MBQB 339 (CanLII)