So... we should be keeping people with criminal minds stoned all the time, because pot has the well-known effect of inhibiting initiative?
What I see in the graph is not a correlation between pot legalization and crime, but a clear relationship between the lax attitudes on crime that began in the 1960s and the more strict measures that started being implemented in the 1990s when people were concerned over high crime rates.
You have to be careful when looking for a causative relationship between correlated observations. Unless a causative mechanism can be established, you might be looking at things that aren’t even connected to each other.
There is indeed a correlation between the two. Crime has plunged while pot laws have loosened. There are now 23 states and DC with medical mj laws. It does not necessarily mean there is causality, but there is definitely a strong correlation.
...but a clear relationship between the lax attitudes on crime that began in the 1960s and the more strict measures that started being implemented in the 1990s when people were concerned over high crime rates.
The strict attitudes on crime, especially drug crimes, began in the early 1980s. It wasn't until the 1990s that drug laws began to loosen. The correlation is weaker. Other correlations are present as well, including strengthening of gun rights and widespread use of the internet. I suspect those have contributed, as well.
The bottom line is that the drug warriors who screamed about rampant crime have been proven wrong. Loose marijuana laws have not led to an increase in crime.