SuttaCentral
While reading the Ākārāṅgasūtra, a Jain scripture hosted at DharmaPaths, I encountered a wonderful and succinct, not necessarily exhaustive, yet highly relevant, definition of karma:
I did it
I shall cause another to do it
I shall allow another to do it
I am not sure it is 100% compatible with the Buddhist definition of karma. 
If it was intentional then it could be. However burning off bad karma by mortifying the body, isn’t. Goenka method of ‘burning off bad sankhara’ sounds a bit like it, but I could be wrong.
With metta
I once read that Jain texts make fun of the Buddhist intention/volition-based model for kamma.
To do that they would raise the case of a man who kills a baby sleeping hidden in a hay stack by sticking into it his sword.
For the jains that is bad kamma for the man.
For the Buddhists, the fact the killing happened without the intent or volition makes that not a bad kamma by the man.
I can recall a sutta which illustrates how Buddhism treats kamma differently from the extremely causist approach of the Jains is the case of the blind monk who steps on creatures while doing walking meditation and said by the Buddha to be free from any bad kamma. Does anyone know the sutta in which this is found? 
I think we frequently justify our intentions with ad hoc mental improvisations after the fact.
I also find Buddhism’s “intentional karma” to leave practitioners particularly vulnerable to convincing themselves, after the fact, that they didn’t really do anything wrong, after mentally reflecting.
However they convince themselves there will be karma. The inability to see what actually took place is all about the practice that needs to be undertaken afterwards.
It should be Ācārāṅgasūtra. The “K” comes in because it was an extremely old translation, made before the consistent style of Romanization was settled upon, so they used k = c. (Actually, italicized k, i.e. Ākārāṅgasūtra, but the italics have been lost.)
The Abhidhamma has a similar idea, they call sasaṅkhārika, translated as “prompted”. By prompting or encouraging someone, we accept some moral responsibility; while if someone does an act instigated by another, their culpability may be lessened.
So, for example, if you have a kid who gets up in the morning and says, “hey mum, let’s go to the monastery and give dana!” They get full marks. But if mum drags them to the monastery and says, “if you give dana I’ll buy you an icecream”, it’s not such a powerful act. As with most Abhidhamma concepts, you can find various precedents for this in the suttas.
But so far as I know the distinction between “cause” and “allow” someone to do something is not found.
I had a vague notion of that distinction as potentially bringing volition into the matter. In a “I intend to do what I do”, “I allow/approve of my action by doing it”, sort of way. Perhaps that is a silly reading.
I have been looking for this sutta and so far only came across what is found in MN56:
“What do you think, householder? Take a Jain ascetic who is restrained in the fourfold restraint: obstructed by all water, devoted to all water, shaking off all water, pervaded by all water. When going out and coming back they accidentally injure many little creatures. Now, what result does Nigaṇṭha Nātaputta say they would incur?”
“Sir, Nigaṇṭha Nātaputta says that unintentional acts are not very blameworthy.”
“But if they are intentional?”
“Then they are very blameworthy.”
“But where does Nigaṇṭha Nātaputta say that intention is classified?”
“In the mental rod, sir.”
“Think about it, householder! You should think before answering. What you said before and what you said after don’t match up. But you said that you would debate on the basis of truth.” “Even though the Buddha says this, still the physical rod is the most blameworthy for performing bad deeds, not so much the verbal rod or the mental rod.”
But this is not exactly the story I was after. Has anyone got a hint of where I will find the case f the blind monk who steps on creatures while doing walking meditation and is said by the Buddha to be free from any bad kamma?
Commentary to the first verses of Dhammapada, the monk’s name is Cakkhupala.
Thank you very much! I thought I was going crazy and making up stories in my mind! 
So below is the story:
The Story of Thera Cakkhupala
While residing at the Jetavana monastery in Savatthi, the Buddha uttered Verse (1) of this book (Dhammapada), with reference to Cakkhupala, a blind thera.
On one occasion, Thera Cakkhupala came to pay homage to the Buddha at the Jetavana monastery.
One night, while pacing up and down in meditation, the thera accidentally stepped on some insects.
In the morning, some bhikkhus visiting the thera found the dead insects.
They thought ill of the thera and reported the matter to the Buddha.
The Buddha asked them whether they had seen the thera killing the insects.
When they answered in the negative, the Buddha said, “Just as you had not seen him killing, so also he had not seen those living insects.
Besides, as the thera had already attained arahatship he could have no intention of killing and so was quite innocent.”On being asked why Cakkhupala was blind although he was an arahat, the Buddha told the following story:
Cakkhupala was a physician in one of his past existences.
Once, he had deliberately made a woman patient blind. That woman had promised him to become his slave, together with her children, if her eyes were completely cured. Fearing that she and her children would have to become slaves, she lied to the physician. She told him that her eyes were getting worse when, in fact, they were perfectly cured. The physician knew she was deceiving him, so in revenge, he gave her another ointment, which made her totally blind. As a result of this evil deed the physician lost his eyesight many times in his later existences.
Then the Buddha spoke in verse as follows:
Verse 1: All mental phenomena have mind as their forerunner; they have mind as their chief; they are mind-made. If one speaks or acts with an evil mind, ‘dukkha’ follows him just as the wheel follows the hoofprint of the ox that draws the cart.
At the end of the discourse, thirty thousand bhikkhus attained arahatship together with Analytical Insight (Patisambhida).
Source: Tipitaka.net
Note: Pali text is found in Tipitaka.org.
