Christy Zartler had practiced what to say, yet she was still nervous on the witness stand. She and her husband had always done what they believed was right for their autistic daughter, Kara. But now, the judge could decide they were criminals, or at least her husband was, and not allow him to be Kara's guardian.

Christy leaned forward, her glasses perched atop blonde bangs, as she listened to her attorney's questions. She glanced at Kara, her 98-pound 18-year-old, seated in a wheelchair by her own attorney in the courtroom in downtown Dallas.

"Mark, your child's father, was investigated by Child Protective Services for having administered cannabis vapor to Kara," her lawyer said. "Do you recall that?"

"Yes," she said, her voice shaking.

Christy Zartler answers questions from her attorney Rick O'Connor in Dallas County probate court. (David Woo / Staff Photographer)

"Why has he done that?" her lawyer asked.

"Kara is a severe case of autism with self-injurious behavior," said Christy, 50, a nurse practitioner. "She punches her head pretty significantly and she has caused brain damage. It prevents her from causing further head trauma and brain damage."

As his wife spoke, Mark Zartler shifted his eyes between her and Judge Brenda Hull Thompson, who sat solemn-faced. She alone would decide the family's fate.

Christy Zartler, on the witness stand, answers questions from her attorney, Rick O'Connor (left) and her daughter Kara's attorney, Ellen Williamson (second from left), next to Kara, in Judge Brenda Hull Thompson's courtroom. (David Woo / Staff Photographer)

If she ruled Mark Zartler "unsuitable" to be Kara's guardian, that could mean big changes for the family. Christy alone would be Kara's guardian, so if anything happened to her, Kara could become a ward of the state. To avoid that, the family would probably move to Colorado or somewhere marijuana is legal. They both have elderly parents to care for, and even so, they don't want to leave. Texas is home.

The lawyer's voice grew impassioned as he spoke of Mark having a child abuse record for trying to protect his daughter by using marijuana.

"In fact, paradoxically, it prevents abuse," he said. "It prevents self-abuse. Is that correct?"

"Correct," Christy said, nodding.

Christy's testimony ended. Their lawyer called Mark to the stand.

As Mark passed his wife, each extended an arm toward the other and they touched hands.

***

Kara, who is unable to speak, usually loves sleeping, but she woke early Thursday in her pink bedroom in Richardson. Her mother was already up too. Maybe Kara could feel the nervous energy in the house.

Christy velcroed Kara's multicolored orthotics onto her feet and ankles, as Kara rocked in her favorite chair in the living room. Mark ran a brush through Kara's short brown hair.

"It's a big day," Christy sang to Kara. "Your hair looks beautiful, girl."

For the occasion, Christy had gone to Target the night before to buy Kara a new outfit. She decided on a loose-fitting floral pantsuit and a special silver necklace.

Under normal circumstances, guardianship hearings are something of a formality for families with disabled children who turn 18. They usually last 10 minutes. The parents, or other guardians, must prove that the person is unable to live independently and that the parents are qualified to oversee the person's life. Someone placed under guardianship loses the right to vote, to marry, to make medical decisions.

But Christy and Mark knew they had made their situation atypical. Their lawyer warned them that they could lose.

Christy and Mark dressed themselves with care, too, thinking about the impression they'd make on the judge. Even though both have long considered themselves Republicans, they were glad they got a Democrat instead of a hardline conservative.

Christy first slipped on a black, white and gray dress. It could send the message, she thought, that their situation doesn't fit into black or white extremes, but exists in a gray area: Giving Kara marijuana is illegal, but not morally wrong.

Christy and Mark Zartler take their daughter, Kara, with them to probate court in downtown Dallas to try to remain her legal guardians. Judge Brenda Hull Thompson ruled in favor of the parents. (David Woo / Staff Photographer)

Mark asked if color would be more optimistic. Christy went with a dress splotched with bright blue, purple, pink and green.

Mark, 49, a software engineer who works from home, didn't have much choice for clothing — he owns one suit that fits. He bought it 27 years ago in college, when he and Christy were dating and he was about to go on job interviews.

Back then, they had no idea the direction their lives would take. No idea that they'd one day become marijuana activists.

***

They started on that path Nov. 10, 1999, with the three-months-premature birth of their twin girls. Keeley developed healthily, but Kara had cerebral palsy and severe autism.

Baby images of Kara Zartler and her twin sister, Keeley, hang in the stairwell of the family home in Richardson. The girls were born three months premature. Keeley developed normally, but at 15 months, Kara was diagnosed with cerebral palsy. (Smiley N. Pool / Staff Photographer)

At age 4, Kara started suffering fits of self-abuse, often smashing her hand into her face. She has broken bones. Her school has recorded her hitting herself 3,000 times in one day; it was considered a good day if she hit under 1,000 times.

Her parents tried every anti-psychotic drug out there. Most of them turned her into a catatonic zombie, they said.

"We could strip away her personality, but it didn't stop the hitting," Mark said.

About seven years ago, a neighbor suggested the parents try marijuana. They scoffed at the idea, but accepted a pot brownie from him. When they gave it to Kara before a road trip, she was calm for five hours and interested in looking out the window — when usually she'd be yelling and punching herself.

Since then, the Zartlers have found marijuana to be the only drug that works for Kara every time. It also has allowed her personality and sense of humor to emerge. Her doctors have told the family it's good they found something that works, but they can't recommend breaking the law.

Last year, the Zartlers felt the political winds could be turning. They figured they, as law-abiding, Christian, Republican Texans, had a shot at being the "poster children" who could persuade lawmakers to legalize medical marijuana for autism patients.

They shot a video of Kara having a fit, and Mark administering marijuana vapor to her using a medical mask. In the video, she quickly stops hitting herself after inhaling the vapor. The video went viral online, drawing than 70 million views. The Zartlers made the local and national news.

The family spent long days traveling to Austin, trudging the Capitol for hours on end, showing lawmakers their video and pleading with them to support a marijuana bill for autistic patients.

Over and over, the legislators and their aides expressed sympathy. But over and over, they declined to take a stand. In the end, nothing that would help the family passed.

The video also drew the attention of Child Protective Services, which investigated Mark and found "reason to believe" he had physically abused Kara. Under state law, physical abuse is defined in part by giving a child an illegal drug.

Over the past year, the Zartlers have seen dramatic improvements in Kara's development, they said. Because of the media attention, she has gotten used to having cameras around. She smiles at the lens and often seems to pose, which delights her parents. She also has learned to use the bathroom by herself and no longer needs diapers all the time — a huge step toward a more independent life.

In the weeks before the hearing, Kara's court-appointed attorney visited the family and read Kara her rights, as Kara walked around the kitchen eating. She gave Kara a spiral-bound book, called "Kara Goes To Court," that explained the upcoming hearing.

Before leaving the house Thursday morning, Christy gave the book to Kara to flip through one last time.

Christy Zartler reads a specially prepared book to daughter Kara to prepare her for probate court. (David Woo / Staff Photographer)

"In the Court, there will be a JUDGE," the page said. "The judge is very nice and will be wearing a long black robe. ... The Judge will make a decision. Everyone must follow what the Judge decides."

Kara grazed her fingers along the photo of the smiling judge.

"There's the judge — who's up for re-election, by the way," Christy said. "We'll see if we vote for her after today."

***

Outside the courtroom, Kara's attorney, Ellen Williamson, acknowledged that the situation was unique.

In her role, she said, she must "start from the position of 'We oppose the guardianship,' because it's the most restrictive thing we do to someone, other than putting them in prison."

Rather than actively contest the guardianship, though, she said she sees her job as making the Zartlers prove that they're qualified.

"They're parents who are doing a good job," Williamson said. "They're in a predicament. It's a bit of a catch-22. You're doing something to be a parent but also doing something that the law doesn't allow. I wouldn't be doing my job to not bring that [CPS] information up."

In the courtroom, the parents' lawyer, Rick O'Connor, brought up Mark's CPS record. O'Connor, 63, knew the Zartlers' struggle all too well — his older brother was also severely autistic and would often bite his own hand.

He read aloud from a court investigator's report, which cited the CPS investigation: "It did not appear that Mr. Zartler uses the marijuana with his daughter in an abusive way."

He asked Mark whether the cannabis was the family's last resort.

"Yes," Mark replied.

Mark Zartler answers questions from his attorney Rick O'Connor in probate court. (David Woo / Staff Photographer)

"Kara's pretty docile today — is that unusual?" the attorney asked.

"She's asleep," Mark said, laughing in disbelief as he looked at his usually-rambunctious daughter's head slumped in her wheelchair. "It's unusual."

***

Judge Hull Thompson was ready to rule.

"The court finds it would be for the protection of the rights of [Kara] as well as in [her] best interest for the court to appoint guardians," Thompson said.

Both Mark and Christy were qualified to be guardians, she ruled.

The parents smiled at each other and swallowed back tears. They raised their right hands and swore an oath to uphold Kara's rights.

Outside the courtroom, Christy tapped Kara's shoulder.

"We did it!" she said. Kara was still asleep. The parents couldn't believe it — not only had they gotten what they hoped for, but Kara didn't make a scene at all. It was the first time she had ever slept in public.

The family's joy was mixed, however. They wished Kara could grow into an adult and take care of herself. They looked at Keeley, Kara's twin, with her car and job and plans for college in the fall, and wished Kara could be there too.

"It's emotional because this is not really a natural thing," Christy said, tears welling. "It's not natural to take guardianship of anybody."

As a disabled adult, Kara can attend high school for four more years. After that, her parents hope, she can live in a group home. It's a natural instinct, the Zartlers believe, to want to be around other people, to be independent from one's parents. Kara, they think, must want that too.