More than half of the time, defendants are found not guilty, and only two or three cases result in prison time.
But when an accused person is found guilty, the result can be devastating.
In Arizona, defendants can face prison time of up to 20 years.
Drug charges can be particularly damaging if they’re used to settle a civil case.
The Arizona Supreme Court ruled in 2011 that the state must pay a $1.8m civil judgment to a man who was convicted of possession of methamphetamines.
In an unusual decision, the court said the man was not entitled to any damages.
“This was an attempt by the Arizona Supreme court to recover damages from Mr Pardo, whose only crime was possession of a drug,” Justice Jonathan Sorenson wrote.
“It is clear that Mr Poto had not been able to prove that the meth was the source of the drug.”
“The consequences of this decision could be enormous,” he added.
The state, however, appealed.
In 2013, the US Supreme Court rejected an appeal from a former inmate, who had been convicted of a methamphetamine-related crime.
Justice Samuel Alito wrote for the court that the defendant was not a drug dealer, and thus did not have to prove the drugs were supplied by a dealer.
“This Court has long held that drug possession by a person charged with a crime is not a separate offense,” Alito said in his opinion.
“That principle has become even more clear as drug traffickers have acquired the means to move and sell drugs online, from a variety of websites and through other platforms.
Alito’s decision in the Arizona case came after a ruling in a 2015 case that overturned a previous conviction of a man for drug possession.
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The law is clear: The state’s conduct here was wholly wrong, and the court should not grant a new trial,” Sotomaysaid.
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