The first, beginning in the 1950s, was the inclusion of the Lieberman clause in the "ketubah" (marriage contract). Named for Talmudic scholar and Jewish Theological Seminary (JTS) professor Saul Lieberman, the clause requires that a "get" be granted if a civil divorce is ever issued. While most Orthodox rabbis have rejected the Lieberman clause, leaders of the Conservative movement claim that the original intent was to find a solution that could be used by Orthodox and Conservative rabbis alike, and that leaders of Orthodox Judaism's Rabbinical Council of America, and respected Orthodox rabbis, including Joseph B. Soloveitchik, supposedly recognized the clause as valid. Later, because some civil courts viewed the enforcement of a religious document as a violation of the constitutional principle of the separation of church and state, Conservative rabbis began to require couples to sign a separate letter, stating that the clause had been explained to them as part of pre-marital counseling, and that both parties understood and agreed to its conditions, recognizing that this letter would constitute a separate civil document, enforceable in a civil court. However, many Conservative rabbis, including some on the movement's own law committee, had growing misgivings about the clause for religious reasons. The second approach fell into the category of conditional marriages, "t'nai b'kiddushin," and was based in part on past approaches used by both the French and Turkish rabbinates—but, according to Rabinowitz—had improvements gleaned from lessons learned from those past experiences. The "ketubah" was not changed, but a separate pre-marital agreement was signed, and in the presence of the rabbinical court, the prospective groom read it, and the prospective bride stated that she agreed to it. The agreement was that the parties understood that if a civil divorce were ever granted, then a get must be delivered within six months of that date. A refusal to abide by that agreement would give the court no choice but to consider the original marriage, and the original declaration of the groom, so flawed that it would be as if that marriage never occurred. The third approach, using contacts both within Judaism and external to it, was to coerce the recalcitrant husband to grant a get. One example cited at the conference was a case where the civilly-divorced husband planned to remarry, this time to a Catholic woman in a Catholic religious ceremony. The Conservative movement's Bet Din contacted the Catholic Church, which agreed to refuse to have the marriage performed until the previous marriage was religiously dissolved, resulting in the almost immediate granting of the get by the husband.