Given the myriad ways canines have been trained to use their powerful sense of smell, it is not hard to imagine they could be taught to differentiate between a large quantity of marijuana and less than an ounce.

Until that time, police may be wasting their time using drug-sniffing dogs as the basis for pot arrests, such as the one on Route 3 last month.

It’s the latest indication that while the state’s 2008 marijuana law may have put the proper emphasis on casual pot smoking, it has created a frustrating barrier between police and their ability to pursue more serious drug crimes.

READ MORE: Editorial: Growing haze of confusion around state’s pot law
Patriot Ledger (Quincy), June 9, 2011