First Woman Charged on Controversial Law that Criminalizes Drug Use During Pregnancy Critics argue law will deter women from seeking treatment.

 -- A Tennessee woman is the first to be charged under a new state law that specifically makes it a crime to take drugs while pregnant, calling it "assault."

Mallory Loyola, 26, was arrested this week after both she and her newborn infant tested positive for meth, according to ABC News affiliate WATE-TV in Knoxville, Tennessee. Loyola is the first person in the state to prosecuted for the offense.

The law, which just went into effect earlier this month, allows a woman to be "prosecuted for assault for the illegal use of a narcotic drug while pregnant" if her infant is harmed or addicted to the drug.

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Monroe County Sheriff Bill Bivens told WATE-TV that the 26-year-old admitted to smoking meth days before giving birth.

"Anytime someone is addicted and they can't get off for their own child, their own flesh and blood, it's sad," he said.

Bivens said he hoped the arrest would deter other pregnant women from drug use.

"Hopefully it will send a signal to other women who are pregnant and have a drug problem to seek help. That's what we want them to do," he said.

The law has come under tremendous opposition from both state and national critics, who say that the law will hinder drug-addicted pregnant women from getting help and treatment.

The American Civil Liberties Union of Tennessee is actively seeking to challenge the law, which they describe as raising "serious constitutional concerns regarding equal treatment under the law."

"This dangerous law unconstitutionally singles out new mothers struggling with addiction for criminal assault charges," Thomas Castelli, legal director of the ACLU Tennessee, said in a statement. "By focusing on punishing women rather than promoting healthy pregnancies, the state is only deterring women struggling with alcohol or drug dependency from seeking the pre-natal care they need."

Just before Tennessee Gov. Bill Haslam signed the bill in April, Michael Botticelli, acting director of the White House Office of National Drug Control Policy at the time, said the federal government didn't want to "criminalize" addiction.

"What's important is that we create environments where we're really diminishing the stigma and the barriers, particularly for pregnant women, who often have a lot of shame and guilt about their substance abuse disorders," Botticelli said, according to The Nashville Tennessean. "We know that it's usually a much more effective treatment and less costly to our taxpayers if we make sure that we're treating folks."

Haslam released a statement after signing the bill saying the intent of the law is to "give law enforcement and district attorneys a tool to address illicit drug use among pregnant women through treatment programs."

Loyola was released on $2,000 bail and was charged with a misdemeanor according to WATE-TV. The law allows anyone charged to use entering a treatment program before birth and successfully completing it afterwards as a defense.

Calls to Loyola's family were not immediately returned.