WASHINGTON — Under crystal-clear skies on a warm autumn day, suburban mother Miriam Carey left her home in Stamford, Conn., to drive 270 miles to Washington, D.C., on a trip from which she would never return.

To this day, no one really knows why she was gunned-down by federal officers in the shadow of the Capitol dome.

The 34-year-old dental hygienist had her beloved infant daughter buckled into the back seat of her black Nissan Infiniti on Oct. 3, 2013, when she apparently made a wrong turn and suddenly found herself at a security checkpoint at the White House.

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The media mistakenly reported that Carey rammed a barrier or a gate, but the initial police report mentions only that she tried to make a U-turn.

Read the initial police report on the Miriam Carey case, Page 1 and Page 2.

No one knows for sure, because, as WND has repeatedly reported, authorities have refused to release all surveillance video of the incident, and still have not even released the official investigation.

Carey's family believes she panicked when officers drew their guns, causing her to flee the scene and lead police on a wild car chase that paralyzed the nation's capital and captured the world's attention, as local, national and international media breathlessly followed the unfolding drama.

The pivotal moment occurred at the Garfield Monument traffic circle, just south of the Capitol, where Carey brought her car to a stop but U.S. Capitol police officers and uniformed Secret Service agents inexplicably failed to use their squad cars to surround her and bring the chase to an end.

Instead, about a half-dozen officers on foot surrounded her with their guns drawn. Carey apparently panicked again and drove off through an opening between the officers. But the police then violated what is standard procedure for most major police departments and fired upon her in a crowded public space.

Police said Carey was mortally wounded by those shots. Although she had the strength to drive away, the chase would come to an end a few blocks away when her car careened out of control at a guard shack, about one block from the Capitol. Officers removed Carey's child from her car, unhurt. Carey was pronounced dead at the hospital.

The media initially reported police suspected Carey to be a terrorist threat. That turned out to be untrue. Then the media reported she was mentally unstable. When that also turned out to be untrue, the media had run out of pat answers and lost interest, never bothering to really ask why the incident happened and investigate the background of Miriam Carey.

Legal and civil liberties experts told WND they have a word for what happened to her: Murder.

In an exclusive interview with WND, Miriam Carey’s sister, Valarie, a retired New York City police sergeant, spoke candidly and movingly about the sister she knew.

Read Valarie Carey's personal plea: Seeking justice for my sister

Her attorney, Eric Sanders, also a former NYPD officer, accompanied her. Tired of waiting for an official explanation of what happened, Sanders informed WND on Jan. 31, that the Carey family has filed a $75 million lawsuit against the U.S. government. As WND has also reported, the mainstream media has ignored the lawsuit, too.

Miriam the person

"Miriam loved life, and she loved her family. She was a very loving and caring person. But she was also very goal-oriented and optimistic," Valarie reflected somberly, while walking the chase route on a clear but chilly winter's day.

Miriam's daughter was the apple of her eye, said the mournful sister, adding, "It was a blessing to have a new niece, and Miriam was really happy to be a new mother."

With a broad smile, Valarie described her sister as having a zest for life and learning, a passion for travel and a love of family and friends.

Pausing to fight back the tears, the soft-spoken sister said, "It just hurts to know that she will not be able to continue her journey."

When asked if there was ever any sibling rivalry, Valarie smiled and even laughed.

"Yes, we were sisters. You know, your little sister is wearing your clothes sometimes. Then there were the academics, you know, things like that," said the big sister, calling Miriam an excellent student.

Valarie could never imagine any reason a police department could have suspected Miriam of any criminal activity.

"My sister was not a criminal. My sister was a law-abiding citizen and she didn’t commit any crimes while she was in the District of Columbia,” insisted the former police sergeant.

As for the media's speculation on Miriam's mental state, Sanders said, "We don’t know of any history of mental illness or drug use, and there’s no objective data to support the idea that there was any mental condition. What it boils down to is that you have a young woman in the District of Columbia and she was killed. That’s the only thing we know."

Sanders said none of that speculation was even relevant and that the only thing that mattered was that "police were not justified in discharging their weapons. So, for us it’s a non-issue."

He had met Miriam a few years ago and described her to WND as vivacious and upbeat, adding, "She was someone you would trust your life. That’s why they’re so confused about what happened here. No one knows."

Miriam’s dreams

"She had aspirations of teaching others who were interested in the dental field. She seemed to have a passion for it. She expressed that she was contemplating going back to school and becoming a dentist herself," Valarie said.

As part of her work, Miriam operated a referral business in which she would connect other dental hygienists to jobs, a task she enjoyed.

Relishing a chance to laugh while remembering her sister, Valarie chuckled at the memory of being "the patient" when Miriam was training to become a dental hygienist.

Valarie bragged about her sister's skills, stating she even trusted her sister enough to be a real patient.

"I had confidence in her. I knew that she was going to be able to handle the tasks, and I was more than happy to assist her in obtaining her goals," Valarie said.

She said Miriam’s dreams fit closely with the profile of the Carey family as people who take pride and pleasure in helping others.

"With me being a civil servant and my other sister, Amy, being a registered nurse and my mother also in the health profession ... that’s something I think we kind of got from our mom," Valarie said.

Valarie remembers long conversations with her sister, and she marveled at Miriam's knowledge on such a wide variety of interests.

"We talked about so many different things, like fashion. My sister was very stylish. And she just enjoyed life, and just her activities. We talked about what we were going to do on the weekends, getting together," Valarie said.

Miriam also had a talent for making people feel good and for enjoying their company.

"She was good at bringing together friends and family. She was good at making people laugh. She was good at debating different topics and really good at keeping family relationships active and positive. She was a bridge to bring people together," Valarie said with pride.

Fighting back tears, Valarie confided, "That’s why we were just looking forward to spending more time together as a family, but now we’re not going to be able to do that. This has just shattered our lives. It shattered our family. It was so unexpected, so unjust, so unfair, so untimely."

"She’s not going to be here to celebrate holidays; she’s not going to be here for birthdays. She’s not going to be here for her daughter. There’s a big empty spot in my life right now," Valarie said.

Valarie again fought back the urge to cry when she talked about how difficult it was to get through the recent holiday season.

"Yes, very rough, for my mom, for us. It was rough. We were looking forward to Thanksgiving at my house and, you know, she was notably missed."

Valarie also recalled happier times, such as the family vacation to Niagara Falls. But that memory, like all other memories of Miriam, has become bittersweet.

"I think what I’ll miss most is just having her there. To be able to have her call me when she has a problem. These are things that you take for granted. It’s not natural for a 34-year-old who didn’t have any medical problems to just cease to exist. That’s not something you foresee. That’s not something that you think about," Valarie said.

For a moment, Valarie sat quietly and reflected upon her family’s anguish about what happened to her sister. She admits that she will never understand why Miriam was killed on that October morning.

"My sister was a law-abiding citizen, so she wasn’t involved in any activities that made me worry her as if her safety was going to be in harm’s way. It’s one of the reasons why this whole thing makes no sense at all," Valarie said.

Where's the outrage?

Sanders wondered aloud about the lack of outrage over the death of someone so normal, she easily could have been anyone's relative or neighbor.

"She was a law-abiding citizen, so it’s unfortunate there aren’t more people who are upset about this because Miriam could be anyone. She was a sister and a daughter. She was a mother. She could be anyone and that’s why this issue should be on everyone’s mind. This could have been your sister, your daughter. Everyone makes mistakes, but she didn’t have to die," Sanders said.

The attorney believes the initial media coverage is one reason there is so little public interest.

"I think what happened is that first she was portrayed as a woman with a gun. That was inaccurate. Then it was a crazy person driving around. Of course, we don’t value crazy people in this world. So we can discard them. She didn’t mean anything, and that’s how it’s been portrayed so far," Sanders said.

Sanders zeroes on the silence from the White House over this issue.

"The president didn’t even comment on it. We’re not asking him to make any particular comment like it’s unjustified. But at least state that there was a U. S. citizen who was killed in the capital. I think that’s something that should garner some attention," Sanders said.

See these WND stories on the Miriam Carey Mystery: