If there is a dispute between two Jewish individuals in a civil matter which they cannot resolve themselves, they must take the matter to a Beth Din (Jewish Rabbinical Court). They may not go to a secular court, even if both parties agree, because it would imply rejection of the Torah.
If one of the two parties refuses to appear before the Beth Din, the common practice is for the Beth Din to summon him three times. If, after that time, the recalcitrant party still refuses to appear, the Beth Din can give permission to the plaintiff to take the case to the secular courts.
When the plaintiff receives this permission he is fully permitted to go to the secular courts without any concern of transgression.
(See Sh. 'A. Hoshen Mishpat 26: 1, 2)
