Marijuana safe?

Why are the Liberals thinking of legalizing marijuana? Is it possible that they don’t know what’s on their own web site where Health Canada has posted serious warnings against its use (Health Canada consumer information cannabis). Is the government blind to the following detrimental effects of legalization in places like Colorado?
 
A) Increased Use: An April 2016 report by the Colorado Department of Public Safety found that although high school use dropped slightly, use by 18 to 25 year olds increased from 21% in 2006 to 31% in 2014 while use by adults doubled.

B) Increased Emergency Visits: As reported in a June 2014 article in the New England Journal of Medicine, between 2004 and 2011, marijuana was associated with a 100% increase in the number of emergency department visits in the U.S. to 129,000 when used  alone and a 62% increase to 327,000 visits when used in conjunction with other drugs. 

C) Automobile Fatalities: Colorado began the process of legalization for medical use in 2006, and since 2013 has implemented full legalization.  Data gathered by the Rocky Mountain High Intensity Trafficking Area in Colorado reported a rise in marijuana-related traffic deaths of 92% from 2010 to 2014.

D) Psychosis: The American Psychiatric Association’s official statement sites a strong association of cannabis use with the onset of  psychiatric disorders and finds that adolescents are particularly vulnerable to harm. Health Canada issued similar warnings.
  
E) Gateway Drug: Marijuana is a gateway drug. Rarely do law enforcement agents meet heroin or cocaine addicts who did not start their drug use with marijuana. For example, the Journal of American Medical Association reported that based on a study of 300 sets of twins, the marijuana-using twin was four times more likely than their sibling to use cocaine. 
 
Is the Liberal government unaware that British Columbia recently declared a public health emergency after a dramatic increase in deaths from illicit drugs in the first 3 months of 2016?  And, does the Liberal’s adherence to ideology trump the harm that will result from use by young Canadians?

Don John