Three Orthodox rabbis are seeking to overturn the 2015 kidnapping conspiracy convictions that put them in prison.

According to authorities, the rabbis used beatings and other extreme means to force unwilling husbands to grant religious divorces to their wives.

On Wednesday, lawyers for the rabbis appeared before a panel of the U.S. Court of Appeals for the Third Circuit in Philadelphia, where they argued that investigators violated their clients' constitutional rights during the criminal investigation and that there were judicial errors during the trial.

Rabbis Mendel Epstein, Jay Goldstein, and Binyamin Stimler had stood trial before U.S. District Judge Freda Wolfson in Trenton and were convicted of conspiracy to commit kidnapping. Goldstein and Stimler were also convicted of attempted kidnapping.

Epstein, 70, of Lakewood, N.J., was identified as the rabbi who orchestrated kidnappings and assaults of recalcitrant husbands. He was sentenced to 10 years. Goldstein, 61, of Brooklyn, N.Y., was sentenced to eight years, and Stimler, 41, also of Brooklyn, to three years.

Ten individuals were convicted at trial or through plea agreements for their parts in the conspiracy.

The assaults were carried out from 2009 through 2013 in New Jersey and other locations, such as Brooklyn, according to court documents. The documents detailed three alleged attacks, in New Jersey and Brooklyn, in which husbands were kidnapped, tied up, and beaten. In one alleged attack, the victim said he was assaulted with a stun gun.

At his sentencing, Epstein told the judge that he got caught up in his "tough guy" image as he tried to get "these reprobates to do the right thing."

On Wednesday, Epstein's attorney, Peter Goldberger, argued that Wolfson erred during the trial by not allowing evidence that would have explained to the jury the rabbi's religious beliefs. His client, Goldberger said, had good intentions of helping the women.

Goldstein's attorney, Aidan O'Connor, argued that federal authorities violated his client's privacy rights when they failed to get a warrant to obtain cellphone records. Investigators used pings between Goldstein's phone and cellular towers to show his whereabouts. A federal judge signed an order to allow authorities to obtain the data, which prosecutors said is legally sufficient.

Nathan Lewin, Stimler's attorney, told the panel of judges that the evidence was too scant to justify a conviction against his client.

Assistant U.S. Prosecutors Norman Gross and Glenn Moramarco argued that the judge had not made errors during the trial, that investigators obtained the cellphone records properly, and that there was sufficient evidence to convict Stimler.

After the hearing, U.S. Attorney Paul Fishman said the three men had been given fair trials.

"The defendants were convicted of what we viewed as reprehensible conduct," Fishman said. "We're hopeful that this court of appeals will see it the same way."

The judges did not rule from the bench, or indicate when they would issue a decision.

Epstein – the author of A Woman's Guide to the Get Process – believed he was helping the wives out of compassion because the women could not remarry within the religion without a get, a religious divorce document, according to court testimony.

The three rabbis were arrested in October 2013 after planning an assault with a woman and her brother, who told the rabbi her husband would not sign a get.

The woman and her brother actually were undercover FBI agents secretly recording their conversations. According to court records, Epstein advised the woman it would require using physical means and it would be expensive – $60,000 – to obtain the get.

"Basically, what we are going to be doing is kidnapping a guy for a couple of hours and beating him up and torturing him, and then getting him to give the get," the rabbi said during an Aug. 13, 2013, phone conversation that was recorded.

He described the torture, including use of a cattle prod.

"If you can get a bull that weighs five tons to move, you put it in certain parts of his body, and in one minute the guy will know," the rabbi said in the recording.

Epstein, who would not be present during the attack, said he would have an alibi for the night of the kidnapping and suggested the wife also be seen in public so she, too, would have an alibi.

On Oct. 9, 2013, the "kidnap team" of eight people wearing ski masks, Halloween masks, and bandannas traveled from New York to New Jersey to meet at a warehouse, the indictment said. They discussed grabbing, dragging, and tying up the husband.

Among the materials authorities found with the team, according to the indictment, were rope, surgical blades, a screwdriver, and plastic bags. They did not find the cattle prod. Epstein's attorney said there never was a cattle prod. Epstein, he said, fabricated the use of a cattle prod in embellishing what would be done to get the husband to cooperate.

The rabbis were charged in a five-count indictment that included charges of kidnapping related to the three men who told investigators they were abducted and beaten. The jury acquitted the rabbis of those charges but found them guilty of conspiracy to commit kidnapping.