Born in the slums, he and his twin sister, Cassidy, had a difficult upbringing and were, as all siblings, often at one another's throats. As is so often the case, they united immediately against perceived outside threats but otherwise had very little in common.
For much of his youth, John ran with a local street gang - the Steel Vipers - but when several of his best friends died during a rumble that was both unnecessary and overly risky, he turned his back on them and walked away. His instinctive curiosity (Curious disad) and refusal to let things lie led to him eventually discovering the individuals responsible for his friend's death. John struggled with the choice at hand - take bloody revenge or find another way to bring them to justice. He chose the latter and began working with local law enforcement (Contact Group) which culminated in a bloody firefight between a couple of street judges and the gang leaders.
Before the dust fully settled from this mess, the Second American Civil began, and John, who at the time both strongly believed in the Independent cause and wanted to get away from the place where he had lost good friends, joined the military at once, but rather than spending any significant time on the front, he was parked mostly in Intelligence. By the end of the war, he was greatly disillusioned with the Independents and had come to the conclusion that both sides of the war sucked.
His final taste of the war came at the Battle of Texarcana where the Independents were crushed. John would like to say that he was a Big Damned Hero there, but the truth of the matter was that he was more focused on staying alive than anything else. His entire command unit was wiped out during the siege, and he himself was badly injured but somehow managed to survive only to end up captured as a POW. As a verified "Browncoat," he then spent several years in a federal prison (Social Stigma: Criminal Record disad) but was released in 2069 when the current presidential administration bowed to pressure brought on by then Senator Palmer to release all such prisoners in an attempt to heal the wounds caused by the War.
The years between 2069 and 2076 are currently left open for GM use. What he was doing during this time depends upon the needs of the campaign. This might be an excellent time for him to be recruited by CTU (providing he's actually a member.) (Secret: undercover CTU agent, total rejection)
By 2076, he had returned to OKC and ended up reuniting with what was left of his family. Shortly thereafter, he got involved in the Ugliness.
And then, the campaign begins...