Abel Koontz was the prime suspect of the murder of Lilly Kane.
Not much is known about Koontz's background. What we do know is that Koontz was the person at Kane Software who perfected streaming media and was cheated out of the patent. He then tried to invent a technology that "would put Kane out of business". He failed, and his wife walked out on him. He also has a daughter, Amelia DeLongpré.
The Lilly Kane murder
Three months after Lilly Kane's murder, Abel Koontz confessed to murdering her. Don Lamb then found Lilly Kane's backpack and shoes while searching Abel's houseboat, backing up Abel's confession. Until this point, Keith Mars's investigation was squarely focused on the Kane family as suspects. It was Keith's failure to investigate Koontz that led to his eventual ousting as Balboa County Sheriff.
A year later, when Veronica Mars started to conduct her own investigation of Lilly's murder, she visited Koontz on death row twice. She was suspicious of Koontz's confession because he fired his attorney while on death row and she discovered that the same shoes that were found in Koontz houseboat were in Lilly's room at the time of the murder. During the first visit, Abel figured out who Veronica was, and told her that Jake Kane was her biological father. Lianne Mars and Jake Kane used to date while they were in high school.
After she met Abel, she sneaked into his doctor's office and stole both his and Duncan Kane's medical files. She found out that Duncan had type-4 epilepsy, whose symptoms included violent outbursts and seizures. For the first time, Veronica realized that Duncan was a possible suspect in Lilly's murder. She also found out that Abel Koontz had stomach cancer, and that he was dying. She concluded that Jake Kane paid Koontz to confess to the murder, even though he was not the perpetrator so that Keith Mars's investigation into the Kane family would end. Koontz accepted the offer because he knew was dying and intended to give the money to his daughter.
During Veronica's second visit to Koontz, she told him that she knew that he was not guilty and that he was dying, and that was why he was paid to confess to the murder. Koontz's innocence was further solidified when Keith went to Las Vegas to talk to a prostitute that was with Abel at the time of Lilly's murder. Koontz was later released from death row.
Disappearance of Amelia DeLongpré
One year after Koontz was released, he returned to Neptune, despite suffering from stomach cancer and staying in the hospital, looking for Veronica Mars and asks her to help him find his daughter Amelia as she has gone missing. Koontz told Veronica he wishes to see her again before he dies.
Koontz returns to the hospital while he waits for Veronica to return with his daughter. Veronica discovers that Amelia was killed by Carlos Mercado. Upon returning to the hospital to tell Koontz about the nature of his daughter's death, Veronica lies to Koontz, telling him that Amelia is overseas and fighting against a snowstorm while probably mountain climbing and she is waiting for a helicopter to rescue her. Koontz smiled and thanked Veronica for telling him that his daughter Is happy. Koontz later died from his stomach cancer.
- 2x06 Rat Saw God