A new study reveals that cannabis legalisation leads to lower grades and lower academic interest for students.
The research found that grades at Washington Western University declined after Washington became the first US state to legalise recreational marijuana in 2012.
In 2018 there were 528 marijuana retailers in Washington – one supplier for every 1.4 Starbucks in the state.
Cannabis use among students went up after legalisation, as did the number of D and F grades.
Researchers Adam Wright and John Kreig, said: “While the pharmacology of cannabis is relatively well understood, much less is known about the impacts of moving marijuana from a controlled substance to one that is legally available.”
The study builds on previous research that shows frequent use of marijuana “is associated with decreased ambition and motivation”.
‘Harmful cognitive effects’
The researchers also refer to a study at the Netherlands’ Maastricht University where student grades improved following the tightening of cannabis laws.
Prof Ulf Zölitz and Dr Olivier Marie, who conducted this study, said “the academic performance of students who are no longer legally permitted to buy cannabis substantially increases” with grades rising by an average of five per cent.
Craig Mackinlay MP, Chairman of the All Party Parliamentary Group on Cannabis: Harmful Effects on Developing Brains, said: “These studies illustrate that there should be no doubt about the harmful cognitive effects that cannabis can have on young people’s development”.
He added: “People of influence need to stop toying with the idea of legalising and realise the impact their misplaced views may have on our future generations.”