Clay Jones of the Fredericksburg Free Lance-Star has written up what either is a case of really similar cartoons or plagiarism. The original cartoon is by Nate Beeler of the Examiner, while the similar one is by Jim Hope, a freelancer for the Culpeper (VA) Star Exponent. Jones linked to a story at the S-E as well, where in the comments Hope maintains it was a coincidence, writing:
The incident of two pieces of art work done by Nate Beeler of the Washington Examiner and the one done by myself was truely coincidental. I had know previous knowledge of Mr. Beeler’s work till I was notified by the Star-Exponent.
After locating Mr. Beeler’s work, I was dumbfounded in the similarities. I contacted Mr. Beeler explaining to him the situation and claimed no right to nore did I plagiarize his work. Mr. Beeler responded, stating, ‘No worries, I’m surprised more people didn’t use that image.’
In my own defense, people in all lines of life come up with the same ideas and concepts, especially in this line of work. I sincerely hope you, the readers understand.
Jones comes down on the side of plagiarism. I honestly have no opinion on this - Nate's a friend, this wasn't a great idea for a cartoon, and I'm not a cartoonist so it's hard to know how inspiration may or may not strike. Certainly I think one can unconsciously borrow an idea that one saw briefly - and the Internet makes it much easier to do that, but also to spot said borrowing. Jones posted the two cartoons as a pdf file as well.
Dave Astor's got this story as well (I didn't get it from him!) - "Cartoonist Loses Freelance Job After Plagiarism Allegation," E&P July 29, 2008.