He was originally the accomplice in crime to Chutney the Butler, before discovering Chutney's plan on double-crossing him and retaliating. Afterwards, he is briefly employed by the NYPD as a police dog and partnered up with Officer Dibble.
A rather rectangular shaped dog, Griswald is thickly built with white fur and a small crescent-shaped tail. His muzzle is a dark shade of tan - almost brown - and his ears are completely black. His head comes up to a triangular tip, with a matching triangular nose, with beady little eyes and a unibrow. He has a noticeable under-bite and wears a red collar.
In his second appearance in the series, Griswald takes on a much more oblong shape and he lacks his under-bite. He is more orange, with a lighter, peach-colored muzzle. His collar is now blue, rather than red.
He is quite a vicious and dedicated dog, but also gullible and noticeably dim-witted. Griswald doesn't take kindly to others trying to pull the wool over his eyes - be it lying to, tricking, or otherwise double-crossing him. He is very literal-minded and will often dedicate himself to any goal he has at the moment with much gusto. He is, however, prone to slipping up and focusing on something else - such as when he was so bothered by Benny's piano playing that he derailed one of Chutney's plans just to correct Benny. In the film, he is convinced by Top Cat that he is, in fact, a cat, which Griswald believes due to his gullible nature. His speech pattern - or rather, minimal amount of speech with occasional giggling - in the original series seems to be based on Muttley.