Charles "Casey" Jones is a U.S. army officer and an old flame of Jane's. He later joins the army and fought in Iraq.
To be updated..
Lt. Col. Jones has returned to Boston in "We Don't Need Another Hero" from a tour in Iraq. He and Jane reconnect during the honoring for her and PFC Abby Sherman. He later visits Jane and sleeps (just sleeps) with her to ensure her safety.
In "Seventeen Ain't So Sweet", Casey was just about to fulfill his promise to Jane to meet at their high school reunion when his squad was called back for a mission. He contacts Jane through Skype and they remain in contact for the following days, once even calling her while at work. Jane updates him about the case of their dead classmates.
It is revealed in "This Is How a Heart Breaks" that Lt. Col. Casey had been back in Boston for months, helping out PTSD patients at the outreach program of the Truce Veteran Center, without telling Jane. After being bothered by it for quite a while, Jane finally comes to see him again and confronts him about it. Casey, initially avoiding having the conversation with her, pushes her away by saying he has nothing to offer her and that he's occupied with his current job. After Jane leaves, it is revealed that Casey is partially paralyzed.
In "Welcome to the Dollhouse", Korsak finds Casey's service dog, Elsie (who Korsak temporarily named Barney Miller), and Maura brings her back to him. She then realizes that Casey has "cauda equina", one that he got from a roadside bomb. He reveals that he returned to Boston hoping to get surgery and that he is on the waiting list for the spinal-regeneration technique the Boston Clinical Trials is working on. When Maura advises him to tell Jane, Casey refuses and asks him not to tell her, saying that working at the center made him see what injuries like his does to couples.
Casey later contacts Jane, who is still slightly depressed about him. They meet at the Dirty Robber and talk about starting over with their relationship and going slow this time. After Jane, who is still not aware of his injury, makes suggestions about how to start their relationship by meeting once a week to run and skate, they realize that Angela, pretending to be Jane, sent a note to Casey telling him to meet and that she doesn't care about his injury. Casey, insulted and hurt, finally tells Jane about his injury and tries to leave. Jane explains to him that he did not write the note, but she wished that he could have at least told her because she wouldn't have cared, as well. Jane insists that his injury doesn't matter and won't affect her feelings for him. Casey believes her and he tells her that he still wants to see her, but he does need time. They agree and separate on a good note, finally giving Jane the temporary closure she needed. Casey, still ashamed of his condition, asks Jane not to watch him leave, but she could not help but watch with tears in her eyes. At the door, he meets Maura who tells him that she knew he wasn't "mean", referring to her previous remark about him being mean for torturing Jane and not telling her about the real reason he was staying away.
Casey then drops by the precinct in "Over/Under" to leave his service dog, Elsie, with Korsak when Jane sees him. He tells her that he is not ready yet, but he is getting closer.
Later, he visits Jane at her apartment, hoping to just quickly say good-bye, but, after Casey tells her that he can but just won't go into her apartment, Jane tells him that if he wants to talk, he will go and meet her upstairs. After initially refusing, he does so anyway. He tells her that he did not become a candidate for the stem cell trials, so he took on a neurosurgeon who thinks he can remove the bone shrapnel and bone shards from his spine. When Jane offers to go through it with him, Casey objects, saying it will not work between them. He then asks Jane if she was with anyone while he was away, and Jane answers truthfully but tells him that it was him she truly cared about. Casey tells her that he knows she will be able to find someone else again. Fully knowing that it is a risky operation, he kisses Jane one last time and tells her to let him go, finally bidding Jane goodbye.
In "No More Drama in My Life", Jane visits Casey in his apartment. He reveals that he could possibly become a full quadriplegic if he undergoes the operation, but he will risk it as he wants to feel her and give her children.
In "We Are Family", Casey returns after what appears to a successful operation. He tells Jane that the doctors misdiagnosed him that they were able to remove the shrapnel from his spinal cord. He then spends the night with Jane and he tells her that he is returning to Afghanistan to help in the soldiers' therapy there.
In "Partners in Crime" Casey returns home to tell Jane he has been made a full colonel and he must now decide to stay in the service to be a general or retire and marry her.
In "Tears of a Clown" Jane and Casey are torn between their respective careers and their own relationship.
In the season finale "You're Gonna Miss Me When I'm Gone" Jane accepts Casey's proposal, since he agrees to retire from the military. Later, though, Jane changes her mind when he takes a job in the Balkans.
- In the pilot, a police officer, then portrayed by Patrick Wenk-Wolff, who Maura calls "Casey" is present and later credited as "Officer Jones". He is not seen again after that, "Casey Jones" on the show is played by Chris Vance from Season 2 onwards. It was never clarified if this Casey was in fact another Casey or not.