Even though the Justice Department announced in January that it was ending leniency on marijuana laws, it has yet to take concrete action against states that allow the drug.
Cook ticked off several Obama administration policies that he said weakened the war on drugs, such as issuing clemency for some drug dealers, reducing criminal penalties, and encouraging federal oversight of more police departments.
"All of this emboldened criminals," Cook said, adding that Trump and Attorney General Jeff Sessions have reversed the Obama policies.
While Cook did not address the possibility of New Jersey's legalizing marijuana, several police officers at the conference said it would be a grave mistake. Marijuana remains illegal under federal law, but police and prosecutors in states that have legalized it have not taken action against users.