Picking an innocent man's pocket

Let us say you and I have witnessed that someone has picked someone else's pocket. You are a bit confused as what just happened and I tell you:

a. What you saw there was picking an innocent man's pocket.
b. What you saw there was the picking of an innocent man's pocket.

Do both (a) and (b) work in this context? I use (b) myself. But I think (a) could work too.

Here is another example:
Someone speaks English with an American accent now and then says:
c. That was speaking English with a American accent.

Would that work?


Many thanks.