Even though an individual cannot act as judge and litigants cannot rule for themselves, there are times when one may decide the application of the law for oneself. For example, if one should see his object in the hand of another, and it is clear that the other's intention is to steal it, damage it or otherwise refuse to return it, he can grab it away and does not have to hold himself back until he can file a complaint with the court. Certainly, if the delay will cause further damage he need not wait. An example of this would be if the other would hide the object and thereby hide his act from prosecution. In this case it is even permitted to strike the robber, if it is impossible to recover the object through other means. Even if no further damage would occur by waiting to pursue the matter through the courts, as by land, which cannot be hidden away, although violence is prohibited in this case, one may still use other means to retrieve control without the permission of the court. However, this dispensation is only available if the individual can clearly prove that he is legally in the the right. If he cannot prove his claim, even though he knows it to be his, he may not act, and the matter must be pursued through the courts. [See Gemara Moed Katan 17.1]
Another qualifier: The above law is only applicable if the individual has no outstanding debts due to the one who holds the object. For if the individual has some obligation to the other, be it something he seized or stole, a debt or an outstanding rental payment, or any similar situation, he must not seize the object or its value in money until the matter is pursued through the courts. In fact, if the case involves a debt, unilaterally seizing payment transgresses an additional Torah prohibition specifically related to that case, as will be explained in chapter 97.
If one is concerned that the possessor will abscond from justice, hide his valuables and claim inability to pay, or will not obey the court, he can seize other valuables as security, with the stipulation that they be returned at the direction of the court when the case is adjudicated. Similarly, should he happen upon his objects while they are in the hands of others, or if the defendant had left a security with him for some other reason, he may take possession of these and hold them until the case is adjudicated by the court, even if there is no fear of the other's absconding. The Zohar, however, warns against holding back an unrelated deposit, and one who is concerned for his soul will heed these words. Rather, one should quickly pursue the matter through the court, and if the other will not pay mind to the court, the court can instruct others to hold the unrelated deposit as security until the case is processed. The laws relating to this will be explained in chapter 73.
The previous section dealt with two individuals in conflict. If a community is in conflict with an individual from among their own the law different. An example would be if a community is claiming from an individual his portion of the town's taxes due the government, and he refuses to pay. If they know themselves to be in the right they may act on their own to collect the funds from him even though they would not be able to prove his liability in a court, since none can testify against him, as they are all interested parties to the case (being responsible to cover his portion.) If the community members are split as to this individual's liability, the community can force him to present a security deposit while they take the matter to court. In addition, a community is always considered 'a legal possessor' compared to an individual, and the burden of proof falls on the individual to prove that he has no liability and should have his deposit returned. Because of this, the community has the choice of whether to appoint representatives to swear that they are owned money (and would not have to return the deposit) or require an oath from the individual (that he has no liability). They can also invoke the rule of 'choosing the most advantageous precedent' (lit 'establish the law for me like...') if there is an argument among authorities as to the law in their case. (Sefer Mi'eros Aynayim)
The above section is only applicable to an individual who is part of their city and when the issue at hand involves taxes, as the ruling government is always considered 'a possessor' compared to the community and will collect regardless, causing a loss to the community if all the individuals do not submit their share. However, if the dispute concerns a non tax issue from an individual of their city or concerns an individual of another city, the community cannot act on their own and must take the matter to a court. The individual is still required to give a deposit, because communal concerns usually drag on interminably as each one expects his fellow to follow up on the issue ("a pot with two cooks is neither hot nor cold"). If the community's conflict is with a Torah scholar the community does not have the status of 'a possessor', even in regards to tax issues.
If the community can only recover their funds though secular courts they may do so, but an individual is prohibited to do so even if he is allowed to take the law into his own hands (as explained in section 1). There are opinions that rule that if the individual had no other option but to proceed through secular courts and he did so it is valid ex post facto.
Finally, once a 'legal doubt' develops as to the ownership of an object seizing it does not confer the legal status of 'a possessor'.
Today there are often situations where one of the litigants in a conflict will tell the other "I will not submit to a court hearing unless you place funds or the object in escrow to guarantee compliance with the court's ruling." If the other refuses, it appears that the law is in favor with the escrow demand, as we do not have any martial authority to enforce court rulings in the current era. If the guilty party should ignore the court, what can be done to enforce its ruling? Rather, the money or object should be placed in escrow and distributed according to the court's ruling. This is generally what we advise now. A proof to this can be seen in the preceding section, where an individual must give a security deposit to the community to ensure that the community will have funds to be paid from when the issue is finally dealt with by the community members and the court. Certainly then, without an escrow option an individual will have no power to collect if the guilty chooses not to pay. While the money or valuables are with the third party (escrow) neither of the litigants are considered 'a possessor' of these funds or objects, and the same would apply if one of them seized these funds or objects from the third party (escrow), as they are in a state of 'legal doubt'.[NOT SURE ABOUT THIS LAST SENTENCE.]
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