Verbal explanations when caught plagiarising

Universities up and down the country seem to be plagued with plagiarism, right across the spectrum of degree subjects. In fairness to students who do work hard on their programming assignments and well deserve their marks, I take various anti-plagiarism measures against those who cheat, both preventative and punitive. Not that it ever stops them, but still. When similarities are detected and plagiarists caught, there are several standard responses that crop up again and again. Here are some of the most common that I've seen:

But I didn't copy!

"Yes, he helped me...but I didn't copy!"
"Yes, I looked at his code.... but I didn't copy!"
"Yes, he did explain bits to me... but I didn't copy!"
"Yes, I borrowed his code... but I didn't copy!"

[This seems to be a particularly rampant excuse when the program code is identical, character-for-character. It is very bizarre hearing students say several things that indicate that they are guilty of plagiarism, whilst also denying it at the same time. Apparently just because they are learning programming doesn't mean that they can do logic.]

Blaming

Blaming everyone that the student can think of. Blaming the lecturer in charge of the course, blaming the tutors, blaming the lack of other help (even if help was in plentiful supply and well-advertised). Also can come with extra topping: accusing the lecturer who discovered the plagiarism of creating a bad atmosphere on the course by discovering evidence of plagiarism.

[Oh yes, blaming the lecturer for discovering plagiarism is really going to help.]

The black-is-white approach

Deny deny deny, even in the face of irrefutable evidence. Student claims that yes this was his program, and yes it produced those outputs. This is even though the program doesn't even compile and therefore can't run and produce any outputs whatsoever.

Naive innocence

"Yes, I gave her a copy of my code.... but I never dreamed that she'd copy it."

[Yes, you said that last time we caught you for collusion. Do you think we were born yesterday?]

Stream of random excuses

Student goes off into excuses about how he was moving house and he has dyslexia and he's been really stressed and he had flu and then he broke his arm and he doesn't understand English very well and didn't realise when the deadline was and he is really desperate and please please don't penalise him.

The best one.

"Yes, I did it. It was wrong. I shouldn't have done it.I'm really sorry."

The only attempt at explanation I like. At least the student has the decency to minimise the hassle involved.