Arba avot nezikin, there are four primary categories of damages, the ox, the pit, the man and fire." (Bava Kamman 2a) As
avot nezikin "their way is to cause damage" and if and when they cause damage the owner must pay the full amount of the damages. In cases where the damage is unexpected, for example a goring ox, or for a more modern example a biting dog, the owner pays only half damages up until such time as this too becomes its norm. This generally happens only after the third time it caused damages - an ancient version of three strikes and you're out.
Ironically damage can become so expected that the burden of responsibility shifts from perpetrator to "victim." Such is the case of regel bereshut harabim, of damage caused by an ox as it walks in a public thoroughfare. In ancient (and not so ancient) times it was common and accepted for animals to roam in public. One who leaves goods in the path of animals should expect to have them destroyed. Only when the damage is done on someone's private property is the owner held liable.
If that same ox were to unexpectedly gore another ox - or a person - the owner would be liable for chatzi nezek, half damages regardless of where it occurred. We cannot hold the victim responsible for the unexpected act of the animal and being unexpected we can no longer blame the owner - even if such occurs in the private domain of his friend.
There is a fascinating dispute as to the reason behind this obligation to pay chatzi nezek, half damage, for unexpected acts of animaldamage. Should we say that by all rights the owner should have no obligation to pay as he did nothing wrong - we can't account for every eventuality - yet in order to encourage owners to be extra vigilant and prepare for the unexpected we impose a fine of half damages? Or shall we say by right the victim is entitled to full compensation for any damages caused by the owner's animal? However as a "first and unintentional offense" we go easy on the perpetrator, demanding that he pay only half damages. While the end result may be the same the process of getting there is much different.
Those gored unexpectedly by an ox are not the only ones who cannot recover their full loss. As we discussed in our last post there is no compensation given for damages caused by a minor. For very different reasons there is also no compensation required for the damage caused by one's slave.
In the case of children it is because one cannot be held responsible for the actions of another, and the child, due to their age, is exempt from payment. Neither of these reasons apply to a slave. However unpleasant it may sound to the Western ear, slaves are considered property of their owner. While they were to be treated with dignity they had no independent existence and from a legal perspective are the extension of their master. Thus by right any damage caused by one's slave should be the responsibility of the owner and would be if not for another overriding consideration. Namely that if the slave gets mad at the owner "he will go and burn his neighbour's crops and cause his master to pay 100 manot every day." (Bava Kamma 4a)
What is most interesting is the Talmud's explanation of why the slave might want to cause damage to his master, namely that "perhaps his master belittled him." It is most common to treat slaves in demeaning manner. Having one person control another is by its very nature demeaning and it is for this reason Jewish law insists a worker may quit a job at any time. Psychologically this allows the worker - whose loss of independence makes him akin to a slave to his superiors - the feeling of control over his affairs.
We often do not realize the resentment we may cause even inadvertently to our subordinates (and our colleagues and superiors too). It is almost unavoidable. All the more reason that we must constantly try to ensure we are most sensitive to others so that those who come in contact with us will seek to build, even more than 100 manot a day.
 Adam muad leolam, a person is always fully responsible and liable for any and all damage they themselves may cause.
This would be in keeping with Judaism's sense of restorative justice where the emphasis is less on punishment and more on ensuring the victim is fully compensated for his loss. Thus one who did not have the resources to pay for what he had stolen would not go to jail but be forced to work for another, aka slavery and his wages garnished to pay for his crime.
 This is a lot of money. If my calculations are correct (see here for detailed discussion on ancient coinage) this is the equivalent of 5,000 shekalim or 10,000 zuzim. Considering that the value of a standard ketuba is 200 zuzim the daily damage is fifty times as much. While we need not take the Gemara literally once again we see how much easier it is to destroy than to build.