Story highlights Use of medical marijuana may cause parents to run afoul of child welfare groups

Cases are handled the same way regardless of the drug, a spokesman says

Marijuana use does not make someone a bad parent, according to an advocate

Most medical marijuana laws do not address the issue

Shawnee's voice is shrill, quavering -- on the edge of desperate. She clutches her 11-month-old son while trying to comprehend the situation unfolding in front of her.

Her boyfriend -- her child's father, Aaron -- is in handcuffs.

"Why are you doing this?" she pleads with police officers standing on the lawn outside her home.

"Your baby doesn't need to be subjected to marijuana," an officer replies, in an audio recording made by Shawnee on her cell phone.

But she could explain: The couple have legal prescriptions for the marijuana in their home. His is prescribed for anxiety and chronic pain; hers for depression and anxiety.

Shawnee and Aaron say their son is healthy and nurtured.

"I told them we had our cards, our prescriptions," said Shawnee, 27. "They didn't want to see them."

Not long after that exchange, according to police video of the family's encounter, a social worker arrived at the home and decided to place the child in foster care. CNN is not using Shawnee and Aaron's last names or the name of their child because of the ongoing child protection case.

"I was pleading with them, 'Look, you guys, I understand your perception, but we are wonderful parents, hardworking members of our community,'" said Aaron, 34.

"They could not conceive of the fact that you can be a wonderful parent, a decent human being, and medicate with marijuana."

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For agencies enlisted to protect children, marijuana in the home has for decades been an invitation for serious speculation about a parent's fitness.

But as the narrative of medical marijuana legalization unfolds across the country, so does a complicated parallel story of patients whose children are being removed to protective custody -- or worse, permanently removed -- ostensibly because of their legal marijuana use. Most medical marijuana legislation does not seem to account for this possibility.

"The judges, the police, CPS (child protective services) have been fighting this war on drugs for so long," said Maria Green, a medical marijuana patient in Lansing, Michigan, whose infant daughter Bree was placed in foster care last year.

"They just can't get it out of their minds that this is an 'evil' drug they have to fight against."

To be sure, each case has unique circumstances, and child welfare officials at both the state and local level do not comment about specific cases while they are in process, or even once they are closed.

Further complicating the picture: While medical marijuana use is legal in 20 states and the District of Columbia, the federal Drug Enforcement Administration classifies the drug as a Schedule I substance with "no currently accepted medical use in the United States" and high potential for abuse.

In cases involving removal of children, medical marijuana found in the home would seem to be barely distinguishable from other Schedule I substances -- such as heroin or ecstasy.

"CPS handles (cases) the same way regardless of what the drug ... is," said Michael Weston, deputy director of public affairs and outreach programs at the California Department of Social Services. "Everything is weighed in reference to, 'Is this a danger to the child? Is there a potential harm to the child? Is this showing signs of abuse or neglect?'"

There have been no substantive studies yet to determine how medical marijuana impacts parenting.

There is early data, according to a researcher, suggesting a small increase in child poisonings among medical marijuana patients in states where it is legal. And early epidemiological data draws a link between medical cannabis use and increased corporal punishment and physical abuse -- but not neglect.

"We really don't know what's going on," said Bridget Freisthler, an associate professor in the department of social welfare at UCLA, who studies medical marijuana use among parents.

"We don't know whether (medical marijuana) affects parenting or whether caseworkers need to be concerned when they find out this is happening in the home."

Parents fighting to maintain custody of their children say the mere presence of medical marijuana is an almost reflexive trigger for removal.

They cite scores of anecdotes concentrated in states where medical cannabis is legal -- children removed from homes where cannabis is used or grown; babies testing positive for marijuana at birth and subsequently removed; children removed because mothers breastfed at the same time that they used medical marijuana.

"Marijuana use does not make someone a bad parent," said Sara Arnold, co-founder of the Family Law and Cannabis Alliance . "It should not be the primary or sole basis for any Child Protective Services investigation."

But simply having a medical marijuana card does not mean that that patient is acting responsibly with the medication; nor does the mere presence of marijuana imply lack of safety, according to experts.

"Medical marijuana as a risk factor by itself doesn't mean the child isn't safe," said Michael Piraino, chief executive officer of National CASA for Children , an advocacy group for abused and neglected children. "Most kids have had risk factors but remain safe.

"But how do you put together all these pieces of information, of evidence, that a child is or isn't safe?"

The answers can be as variable as the homes where medical marijuana is used.

Piraino says issues related to medical marijuana use and parenthood have started to come up for his agency, but not yet in a significant way.

He notes that any drug in the home carries risks, including potential lack of attention to children's needs and physical danger stemming from possible ingestion, but that the extent of those risks with medical marijuana is not clear.

Aaron and Shawnee bristle at the ongoing debate about their parenting, and worse, the notion that their use of cannabis could raise concerns about abuse or neglect of their child. They say their son is healthy, happy and nurtured.

What brought police officers to their home in early January, they say, was an anomaly -- a loud argument. The clamor was heard by a neighbor, who called the police.

When officers later entered their home to investigate, they discovered loose marijuana, cannabis oil, and marijuana cigarettes strewn on the desk in the couple's living room. The living room smelled like marijuana. (Aaron says the smell was lingering from the couple medicating the night before, after their son fell asleep.)

"What I want you to understand is your baby doesn't need to be subject to marijuana," said one officer in the police video.

Shawnee responds, "What makes you think he is?"

"Because your house really smelled bad of marijuana," said the officer.

The smell of marijuana, a home in a disarray, medical cannabis that was visible -- albeit out of the boy's reach -- are the roots of the ongoing case against them.

"We would never allow our children to get into our medical marijuana," said Aaron, adding that he believes stigma against the plant is at the heart of his and other cases. "If (law enforcement and CPS) had come in, even if it was a couple of empty beer bottles or a wine bottle, I don't think anybody would have raised an eyebrow.

"I had the impression that we had turned this corner," he added. "That we had moved past that stigma."

"Is the child happy? Is the child loved? Is the child well cared for?" said Arnold, who stressed that she has no specific information about Shawnee and Aaron's case, but views it through the lens of countless other families she's counseled. "Marijuana on a desk does not mean they're abusing or neglecting the child."

Nor does growing and using marijuana, said Green, the Michigan mother whose 6-month-old daughter was removed from her custody for two months last September.

According to Michigan law, both Green and her husband, Steve, are allowed to use cannabis medically -- she to treat multiple sclerosis, her husband to treat epilepsy. And she is allowed to grow a certain number of plants to supply to other patients.

Green says the plants were grown behind a locked door -- the children never had access to them -- and the couple never medicated in front of the children. They kept the marijuana they used locked up.

She says a custody battle with her ex-husband, involving a son from a previous marriage, led CPS to her door, and she says despite the pains they had taken to shield their children from the marijuana, Bree was removed from the home and assigned to protective custody.

A major issue debated during the case: whether marijuana plants grown in the Green home increased the danger of armed robbery and thus posed a serious safety issue for children in the home -- in other words, whether theoretical risk of harm to a child constitutes a serious safety concern.

Green and other advocates say that theoretical, potential risk is not enough.

"I find it very scary that parents can have children taken away for something that's a potential," said Arnold.

As a consequence of Bree's removal, Maria and Steve Green were ordered to stop using medical cannabis. She says she suffered some pain and had to use a walker at intervals, but Steve was worse off. He suffered nine or 10 seizures during the two months Bree spent in foster care.

"You've got these parents having to choose between their medicine and their family," said Arnold. "That's an impossible choice, especially if your medicine makes you functional enough to parent."

Green says that medical marijuana patients may not realize the risk of a run-in with CPS. She advises patients not to become too lax, and to realize that not everyone -- including law enforcement, CPS, and the judicial system -- views the marijuana plant through the same lens.

"Think about what are you doing with the meds, where are you smoking, who is watching your kids when you're smoking or under the influence?" said Green. "Have those things in place."

"My advice to parents is to really go out of your way to make sure (your children) are not exposed to it."

After spending a few days in jail -- and their son spending 12 days in foster care -- Aaron and Shawnee say they now understand.

They are setting aside their views about marijuana as a medical treatment, and view it -- at least temporarily -- as a potential barrier to maintaining their family unit.

That does not ease their confusion about the law, or their conviction that the plant has medicinal value.

"There are families out there ... destroyed over a medicinal plant," said Aaron. "It's baffling."