We're not talking about de-criminalization, or police de-prioritization.

We're talking about alcohol-style regulation and sale of marijuana to adults, age 21 and up. We're talking about legally allowed personal cultivation, state/local taxation of retail sales/distribution, and re-evaluation of sentences/records for people charged with marijuana offenses.
We're talking about outright, full-on legalization of marijuana. And in the world's sixth largest economy, that means billions of dollars. 

If California's Proposition 64 passes on November 8, and sales begin by January 1, 2018, California's looking at an additional $1.5 billion flooding into the marijuana market. That number swells to just shy of $3 billion in 2019, and nearly $4 billion by 2020, based on the latest report from New Frontier Data and ArcView Market Research.

And to be clear, that's on top of the already booming medical marijuana market — the total size of the cannabis market would reach $4.27 billion in 2018, and would grow to $6.45 billion by 2020.
The ballot initiative has overwhelming support in California: Over 60% of respondents support Prop. 64, compared to just 34% opposed, according to Ballotpedia's average of polls.

Eoin Treacy's view

Evidence from companies like GW pharmaceuticals and others means that the Drug Enforcement Agency’s (DEA) assertion cannabis is a Schedule 1 narcotic with no medical use and a high probability for misuse is looking increasingly outdated. Arguments for full legalisation go a step further and promote the view cannabis is no more dangerous for consenting adults than alcohol. Considering the damage abuse of alcohol is capable of that’s not a particularly high barrier. 

I’ve never smoked anything so perhaps I’m not the best person to weigh in on the merits or otherwise of cannabis but it is hard to argue with the fact recreational use is expanding, a significant cannabis culture exists and those who want it have no trouble accessing supply. Legalisation looks increasingly likely and cannabis related shares are responding. 

Cannabis related pharmaceuticals companies have some of the larger and more liquid shares. GW Pharmaceuticals is currently testing its highs near 700p and is somewhat overbought in the short-term. A sustained move below the trend mean would be required to question medium-term upside potential. 

Zynerba is a much smaller development stage pharmaceutical company but broke out of a medium-term base this week. 

If cannabis is legalised home growing is likely to become a demand driven business and hydroponics companies like, Colorado based, Aero Growth Corp may benefit. The share has held a progression of higher reaction lows since January but is somewhat overbought in the short term. 

Terra Tech Corp is also involved in the hydroponics sector and its share is currently testing the region of its trend mean. 

Cannabis Sativa is developing edibles and lotions/creams from cannabis and its share exhibits a rounding characteristic consistent with accumulation.