TV
The episode in question aired at 10.30pm on BBC One and featured Tate and a family from Northern Ireland exchanging gifts of "terrorist paraphernalia" including knuckle-dusters and balaclavas. More than 100 viewers complained about the show.
However, Ofcom didn't uphold the complaints, saying the sketches were to be expected from the show.
"Overall this episode was typical of The Catherine Tate Show and would not have gone beyond the expectations of its usual audience," the Ofcom ruling said.
It continued: "In Ofcom's view it would have been clear to the audience that, in a comedy show such as this, exchanging Christmas gifts of terrorist paraphernalia was absurd in the extreme."
The body added that viewers not familiar with the comedy programme were given adequate warning about the content prior to broadcast.
The Christmas one-off of The Catherine Tate Show is expected to be the last. Tate is currently starring as Donna Noble with David Tennant in BBC One's Doctor Who.
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