Charges against Hamilton lawyer Ira Greenspoon in a medical marijuana case involving the Gravelle crime family have been withdrawn by the Crown.

Court documents show that Greenspoon, 56, no longer faces any charges flowing from an 18-month Hamilton police and RCMP investigation into the use of Canada's medical marijuana program as a front for alleged drug trafficking. The probe led to charges in March.

Greenspoon originally was charged with counselling in the commission of an indictable offence, false pretense and participating in a criminal organization. Andre Gravelle, 49, remains charged with conspiracy to traffic marijuana, cannabis oil and hashish, but has also had the charge of participating in a criminal organization dropped, along with charges of counselling in the commission of an indictable offence and false pretense.

The case saw police find 240 mature marijuana plants growing inside truck trailers at two Beach Road addresses, near Kenilworth Avenue North, during searches in the fall of 2012.

Police allege that licences to grow pot under Canada's medicinal marijuana program were being used in an operation that distributed and sold the drug illegally. Police said plants were being grown under a dozen licences, despite the fact that Health Canada stipulates there can only be four licences at one address.

Health Canada is changing the licence system to replace personal production with licensed commercial producers, who are inspected and audited by the federal department.

All charges of participating in a criminal organization against others in the case were also withdrawn. Charges of production of marijuana were withdrawn against Joseph Cuvelier, 48, Bradley Huffman, 42, and Lawrence Mulholland, 49, all of Hamilton. Charges of false pretense were withdrawn against Daniel Gravelle, 56, Andre Leo Gravelle, 20, and Bruce Kenner, 54, also all of Hamilton.

At the time of the arrests in March, a Health Canada spokesperson said cases where the medical marijuana system results in criminal charges is part of the reason why the system needed to be changed. Ottawa recently issued the first licences to produce and distribute medical marijuana under the new rules to Saskatoon-based Prairie Plant Systems, which has been Health Canada's only supplier of pharmaceutical-grade marijuana for 13 years.