user5763: If I do not know the rules of a country, that does not count for that much in a court of law. I will still be punished for breaking the law. Likewise, if I do not know that bad speech results in bad karma will I be punished (in the sense of bad karma in the future )? Or maybe if I don't know what bad speech is will I be punished? To put the most extreme example, if I murder millions of people but I have a brain disorder and don't realize that is wrong, then will I be punished in the future by karma?

user295: Being ignorant of the repercussions is the very reason what we accumulate Karma which will give future experiences which the receiver perceive as unfavourable or painful, hence this this sense it can be considered a sin. 

user7233: If you are ignorant of the cycle of day and night, or the phases of the moon, or even of gravity, your ignorance does not prevent them from happening. Universal laws are just that -- universal -- and they don't change for those who don't know of, understand, or follow them.
There is an element of intention behind all karma/action, and this intention factors into the quality of the actions. A wrong action done with pure intention is certainly less bad than a wrong action done with evil intention, but it's still a wrong action. The "brain disorder" example is interesting, but again, ignorance of universal laws does not halt or change the manifestation of the laws. One can never escape the effects of one's actions, regardless of the circumstances.
Even Angulimala could not escape the accumulation of karma from his time of killing:

Being an arahant, Angulimala remained firm and invulnerable in mind and heart. But his body, the symbol and fruit of previous kamma was still exposed to the effects of his former evil deeds. As an arahant, he needed no words of consolation, but a reminder of the kammic concatenation of cause and effect, which still has to be endured until the end.


5763: <p>If I do not know the rules of a country, that does not count for that much in a court of law. I will still be punished for breaking the law. Likewise, if I do not know that bad speech results in bad karma will I be punished (in the sense of bad karma in the future )? Or maybe if I don't know what bad speech is will I be punished? To put the most extreme example, if I murder millions of people but I have a brain disorder and don't realize that is wrong, then will I be punished in the future by karma?</p>
 295: <p>Being ignorant of the repercussions is the very reason what we accumulate Karma which will give future experiences which the receiver perceive as unfavourable or painful, hence this this sense it can be considered a <a href="https://en.wikipedia.org/wiki/Sin" rel="nofollow">sin</a>. </p>
 7233: <p>If you are ignorant of the cycle of day and night, or the phases of the moon, or even of gravity, your ignorance does not prevent them from happening. Universal laws are just that -- universal -- and they don't change for those who don't know of, understand, or follow them.</p>

<p>There is an element of intention behind all karma/action, and this intention factors into the quality of the actions. A wrong action done with pure intention is certainly less bad than a wrong action done with evil intention, but it's still a wrong action. The "brain disorder" example is interesting, but again, ignorance of universal laws does not halt or change the manifestation of the laws. One can never escape the effects of one's actions, regardless of the circumstances.</p>

<p>Even <a href="https://en.m.wikipedia.org/wiki/Angulimala" rel="nofollow">Angulimala</a> could not escape the accumulation of karma from his time of killing:</p>

<blockquote>
  <p>Being an arahant, Angulimala remained firm and invulnerable in mind and heart. But his body, the symbol and fruit of previous kamma was still exposed to the effects of his former evil deeds. As an arahant, he needed no words of consolation, but a reminder of the kammic concatenation of cause and effect, which still has to be endured until the end.</p>
</blockquote>
