Technically, you did commit a form of theft by taking breaks on the clock and being paid when you were not working. However, it is highly unlikely that even if your employer wanted to press charges that the authorities would do so--they tend to view matters like this (despite it being a form of theft) as "civil," not criminal matters. So charges, being convicted, or facing jail time (since even if convicted, you'd likely get a fine or probation) is unlikely--possible, but unlikely. As to a lawsuit: if you cost them several thousand dollars in time, they may sue you--it could be worth their while. If only several hundred or less, they are very unlikely to think a lawsuit is worth their while.But in answer to your original question: resigning does not mean you cannot prosecuted or sued, since your theft of time still occured. It's just that it is rare for such things to be done in cases like this, unless again, a very large amount of time/money is involved.