The legal battles surrounding cannabis in the 1960s were influenced by changing cultural and political attitudes towards the drug. Reports commissioned by presidents Kennedy and Johnson concluded that marijuana use did not lead to violence or the use of heavier drugs. The bipartisan Shafer Commission also recommended the decriminalization of personal marijuana use. However, a parent’s movement against marijuana led to the 1980s War on Drugs under President Reagan, reinstating mandatory sentences for drug offenders. Since then, there has been a major shift in public perception of marijuana, leading to state-level decriminalization and legalization efforts.