Jason "Jay" Allen (1948 - 1990) was the son of Henry and Nora Allen and the older brother of Barry Allen. He was a Commander of the Central City Police Department up until his death at the hands of Nicholas Pike.
- Jay's name originates from that of the first Flash in the comics, Jason "Jay" Garrick.
- Because of this, Jay's name is now a combination of the names of two Flashes: Jay from Jay Garrick and Allen from Barry Allen.
- Ironically, John Wesley Shipp, who portrays Barry Allen, would go on to play Jay Garrick/The Flash in the 2014 adaptation of the Flash. The Earth One doppelgänger of Garrick is Barry's father Henry, hinting that Barry and Garrick are of the same family, similar to this show where Barry and Jay are family.