Buying a joint could soon be as easy as buying a drink. Last week, the governor signed a law that makes possession of less than an ounce of pot into a minor infraction with a maximum fine of just $100.
It is still illegal to sell marijuana unless it is for medical use, but that could change.
Joseph McNamara was San Jose police chief for 15 years. Now he is a fellow at Stanford University's Hoover Institution.
"Let's be honest, the drug war against marijuana has failed, anyone who wants marijuana in California can get it and yet we keep doing more and more of what has not worked," he said.
McNamara is supporting Proposition 19. It would allow anyone over 21 to have up to an ounce of marijuana. People could also grow a limited amount at their home.
Smoking pot would be banned in public, at schools and in front of minors.
Commercial production and sale of marijuana would be allowed too, but for that, each city and county would create their own regulations and impose taxes.
"It's a golden opportunity for California voters this election day to strike a blow against the drug cartels and drug gangs and to greatly reduce violence and crime that flows from the prohibition of the drug," McNamara said.
The city of Oakland is already taxing medical marijuana and making plans to permit large scale industrial growing.
Selling pot for recreational use could mean a lot more tax money for any community that OKs it.
The state legislative analyst estimates marijuana taxes could bring in hundreds of millions of dollars a year.
Supporters say legalizing pot would also save money by freeing police and prosecutors to tackle other crime.
"Our prison population has people there for marijuana possession charges and dealing that should not be in prison," Former St. Senate President Don Perata said.
But opponents paint a very different picture. Pete Dunbar is police chief in Pleasant Hill.
"Price will go down and consumption will go up which means more people will be under the influence of marijuana, which means more people will be under the influence of marijuana driving a car," he said.
The two sides also disagree on the finances. The 'no' campaign says Prop 19 could cost the state because it violates federal law and that means Washington could try to withhold money from state programs.
"Going against federal law is not something you want to do when you have $9.8 billion tied to education and drug free work place; that money could be gone," Dunbar said.
The Obama administration has not said what it will do if Prop 19 passes.
Some cities and counties may decide not to allow marijuana sales. Dunbar believes there will still be a black market for pot in those areas.
"There's going to be all kinds of different regulations city to city, county to county and we're not going to know each other's rules so it's going to be very confusing for the state," Dunbar said.
To counter that, San Francisco state Sen. Tom Ammiano is already introducing a bill that would create uniform rules for any city or county that allows pot sales.
Supporters believe marijuana smoking may actually go down if Prop 19 passes. They point to the Netherlands where marijuana is legal, but consumption is lower than in the United States.
Opponents are not buying it and say Prop 19 sends the wrong message.
"We will be hurting our young people; on the one hand we are telling them not to smoke, on the other hand we are telling them that using drugs is fine," Frank Lee of the Organization for Justice and Equality said.
Under Prop 19 giving or selling marijuana to anyone under 21 would still be a crime, as would driving under the influence of marijuana.
Written and produced by Jennifer Olney