A cop walks around a corner and catches a man smoking a joint.

"Really sorry, officer," he says, stubbing it out, "but I swear I was just smoking it for a friend."

No, that doesn't make a lot of sense, and it doesn't mitigate the crime. But that's basically the excuse offered by bestselling author Josh Linkner when he was recently busted for plagiarizing the opening paragraphs of a blog post by Chris Dixon.

To his credit, Linkner responded quickly on Twitter and in the comments of Dixon's post. He apologized for what happened. FastCompany and Linkner also moved quickly to change the offending post. (Unfortunately, they didn't add an editor's note acknowledging that the original version included plagiarized material...)

But even more notable is what Linkner said to Dixon in the comment he posted to apologize for what happened:

Hi Chris. Josh Linkner here, the author of this piece @ Fast Company.  I owe you a HUGE apology!!  A friend of mine sent me that excerpt and I had no idea it was yours or anyone else's so I didn't attribute it when I wrote my post. As an author, VC, and entrepreneur I hold myself to the highest standards and I'm deeply sorry this happened.  Will correct and cite you ASAP. Again, honest mistake and I'm sorry it happened.

I was smoking it for a friend! Or: I meant to plagiarize from my friend!

This is what I call the Maureen Dowd Plagiarism Defense, and it only serves to cast more doubt on the person who uses it to explain their actions.

In 2009, Dowd used close to 50 words from a John Marshall post on Talking Points Memo. She didn't offer any attribution. The words were presented as her own, and that led to accusations of plagiarism, and to a correction being issued.

The Dowd Defense emerged when she reached out to a variety of websites to explain how it happened. This is what she told Huffington Post and others:

i was talking to a friend of mine Friday about what I was writing who suggested I make this point, expressing it in a cogent -- and I assumed spontaneous -- way and I wanted to weave the idea into my column.

but, clearly, my friend must have read josh marshall without mentioning that to me.

See, officer, she actually meant to steal from her friend.