Caroline: I grew up with nothing, Cherie. No one should have to fight like I did just to get a decent education.
Her first appearance was in the first season episode, "The Man in the Morgue", which was followed by three more appearances in the second season in "Judas on a Pole", "The Man in the Mansion" and "Stargazer in a Puddle". She has a very demanding and bossy attitude, which overpowers even Brennan to a point where Brennan does not even argue with her. She has a deep understanding of the workings of the government and the way cases should be handled, she seems to have a friendship history with Booth and trusts in his instincts and beliefs when working on cases, although she often seems wary of their less orthodox methods. She has appeared numerous times to have Booth and Brennan in court and to solve their cases. She revealed to Booth in "The Teacher in the Books" that she struggled to become who she is now and that she is on the board of the United Teaching Fellows.
In "The Knight on the Grid," Caroline clashes with Brennan over her brother Russ. While Brennan wants Caroline to recommend parole for Russ who turned himself in after learning that his step-daughter was sick, Caroline refuses as Russ is a material witness in the murder trial against Max Keenan and she sees him as too much of a flight risk. In a later informal meeting with the judge, Caroline argues against parole even though Russ' parole officer Erica Davis is on his side despite reporting the parole violation in the first place. After the judge reveals that he has been contacted by the local archbishop and Lance Sweets on the issue, Caroline realizes that Booth had them intervene. Caroline objects to the relatively light sentence suggested by Erica, but is overruled by the judge who agrees. Afterwards, Caroline tells Booth off for his actions, feeling that such interventions are why the justice system doesn't always work.
In the alternative reality in Booth's mind episode "The End in the Beginning", Caroline works for Booth and Brennan's night club as their legal counsel.
In "Harbingers in the Fountain", when the team is able to identify Tom Fargood as a mass murderer but can't find enough proof to arrest him, Caroline comes up with a list of alternative crimes to charge the man with that will put him in prison for around a hundred years. Caroline reminds Booth and Brennan that although it seems like it around them, murder is not the only crime out there.
Not much is known about Caroline's family life. She was once married to David Barron, a defense attorney who has also served as her main opponent in court, and they have a daughter who studied at MIT during season 2. She is revealed to be divorced in season 8, "The Blood From the Stones". She has also developed a new relationship with a man named Andrew Jursic.
Although her place of birth and background have not as yet been discussed explicitly on camera, Caroline calls those close to her "cher(m)/chérie(f)" and is prone to making references to New Orleans and the Gulf Coast. She first appeared in New Orleans in the wake of Hurricane Katrina. She has a pronounced sweet tooth in her early scenes, ordering a beignet in her first moments, and later guarding her plate of doughnut holes from Booth in "Judas on a Pole" until she herself feels ready to share.
She drives a 40 year old yellow AMC Gremlin with synthetic-panther-covered seats. Although it has an accident almost destroying the front part, during season 2 (in "Judas on a Pole"), it's seen again in later seasons.
In "The Mastodon in the Room", Bones observes that Caroline is "the lynchpin" of the group, having been responsible for getting them all back together after they went their separate ways at the end of Season 5, a charge which Caroline, with a twinkle, refuses to understand. Bones declares that "I find I want to hug you", at which Caroline recoils, and requests the returning Booth not to "leave me alone with her".
In "The Teacher in the Books," Caroline becomes particularly invested in the murder of a teacher, asking Booth to extra careful with it. Caroline explains that she is on the board of the United Teaching Fellows who "do God's work for inner city communities." Caroline worries that if word gets out that its not safe, the whole program could suffer. Booth reassures Caroline that he doesn't intend to let one psycho ruin the kids the program could help, pleasing her. Caroline is able to give Booth the information on the principal and the other UTF teacher the victim worked with and even made sure they knew he was coming. Caroline states that she grew up with nothing and no should have to fight the way she did just to get a decent education. Booth points out how great Caroline turned out and reassures her that he's handling the case. Caroline follows the case closely, hovering over Aubrey much of the time, but being grateful for Booth's way of handling the delicate case. The killer is ultimately proven to be the other UTF teacher who the victim, who was well-loved by everyone, had discovered was falsifying test results so he could get a better job. Caroline decides to take the victim's star student and his older brother under her wing after seeing just how much they were struggling. Caroline promises to tutor the young boy herself and to make sure that his brother gets his GED as well and stays out of trouble. The two promise not to let her down. Bones also uses her new Twitter account to draw attention to Caroline's teaching program, causing some of her followers to donate to it.
In "The Next in the Last", after finding out that Booth and Brennan intend to retire after solving the latest mystery, Caroline gets emotional and tells Booth that no one can replace him. Caroline lends her help in pressuring the head of a corrupt investment firm at Booth's request and says a tearful goodbye to them when they leave along with all of their other friends.
In "The Day in the Life", Caroline attends Cam and Arastoo's wedding. She later acts as the prosecutor in Zack Addy's appeal for the murder of Ray Porter. After Hodgins brings forth new evidence pointing to the Apprentice as the killer, Caroline argues against his release for the victim's family, enraging Hodgins. Ultimately, Zack is exonerated for Porter's murder but must still serve out the remaining thirteen months of his sentence for aiding a known killer, gaining a satisfied nod from Caroline. Brennan then thanks her, having understood that Caroline was merely doing her job but did so in a way to ensure Zack's exoneration by reminding the judge of the new evidence nineteen times. Caroline is surprised by Brennan's insightful remark and warns Zack to stay out of trouble.
In "The End in the End", Caroline looks after Booth's children in the aftermath of the explosion and tells Aubrey to get Kovac, dead or alive though she prefers dead. Due to the threat from Kovac, Caroline wonders half-jokingly if Judge Judy needs a prosecutor while contemplating running away to safety. After Kovac's death, Caroline visits Booth and gives him a relieved hug before telling him that she will ensure that Jeannine Kovac will never be set free from prison. Caroline expresses her regrets that Aubrey and Jessica broke up before leaving.
- Her mother wanted her to go into modern dancing. (The Mystery in the Meat).
- She has implied that she came from a disadvantaged background--she joined the board of the United Teaching Fellows because she wanted to help other children who grew up the same way she did.
- She helps tutor disadvantaged children.
- She considers Booth to be the best FBI agent she's ever worked with.