John Dawlish was a very capable and self-assured auror. He left Hogwarts with Outstandings in all his N.E.W.T.s. He accompanied Fudge to Hogwarts to confront Harry about his secret D.A. meetings. Dawlish was knocked out along with Kingsley Shacklebolt, Dolores Umbridge, and Cornelius Fudge when Dumbledore, who had taken the blame on himself, escaped. Dawlish is described as a “tough-looking wizard with very short wiry hair;” his hair is grey (OP27). According to Snape, Dawlish was susceptible to the Confundus Charm (DH1). In the spring of 1998, Death Eaters sent Dawlish to try to take Augusta Longbottom into custody. It doesn’t go so well for Dawlish. As a result, a few weeks later Dawlish is still in the hospital (DH29).
The name "Dawlish" almost certainly came from the name of a seacoast town in Devon. It is located near Exeter, where JKR attended university.
Rowling named Dawlish 'John' for Leaky Cauldron Creative Director John Noe (PC/JKR1).