Three days before the beginning of Passover, Rabbi Yaakov Horowitz, a veteran mashgiach (kosher supervisor) for the Orthodox Union (OU), filed a lawsuit against Manischewitz and the OU, saying he can no longer stand behind the kosher status of the Manischewitz products he has supervised for 20 years, including its Passover matzos.

“I believe this is a breach of public trust. I just couldn’t handle it,” Horowitz told the Journal on April 21, two days after he filed suit in the New York State Supreme Court.

Within the kashrut world, and particularly when it comes to Manischewitz, Horowitz is seen as a knowledgeable authority. The OU website’s “Getting to Know Your Matzah” article — which gives the ins and outs of matzah kashrut — was written by Horowitz, and he has been interviewed on numerous occasions by major news outlets as a source for Passover kashrut in general, and Manischewitz specifically.

Since 2014, Manischewitz has been owned by Sankaty Advisors, an arm of the private equity giant Bain Capital. In March 2015, when The New York Times’ “Dealbook” section published an article on Manischewitz’s ownership, it quoted Horowitz praising Sankaty’s executives for having “shown a concern for kosher in a special way.” When contacted on April 21, a spokesperson for Bain Capital referred to the Orthodox Union for comment.

Horowitz now alleges, however, that since 2009, Manischewitz’s 200,000-square-foot plant in Newark, N.J., has intentionally bypassed OU kashrut guidelines on several occasions, and that the OU consistently did not support him when he raised concerns. In his lawsuit, Horowitz says OU personnel told him the OU was “feeling pressure within the kosher food industry” because it had lost some accounts to other kosher certifiers.

Horowitz also alleges that when he told the OU that the Manischewitz president warned him that his “job would be in jeopardy if he did not lower kashrut standards,” the implicit message he received from the OU, his employer, was that he needed to “keep Manischewitz happy.”

Both in the lawsuit and in the interview with the Journal, Horowitz listed specific incidents he thinks the public should be aware of, and he said he left the job in December because he could no longer in good faith stand behind OU’s kashrut seal for Manischewitz.

Manischewitz manufactures hundreds of items year-round, and is a massively popular supplier of Passover items such as matzo, wine, gefilte fish and macaroons.

Manischewitz has not yet responded to a request for comment, but the Orthodox Union released the following statement:

“The allegations in this suspiciously-timed lawsuit are entirely without merit, and we will contest this matter vigorously. We certify that the Kashrut of Manischewitz is today, and has always been, at the highest level. Consumers can confidently rely upon the integrity of the Kashrut this Passover and throughout the year.”

Among the most recent of the alleged kashrut violations is from December 2015, when Horowitz says Manischewitz accidentally ran a non-Passover product on its Passover macaroon line, contaminating the entire line, according to OU standards. Horowitz alleges the plant manager did not tell him or other OU personnel about the contamination, allegedly tried to kasher the equipment himself and then continued production. Horowitz said that when he found out about the issue and reported it, the OU excluded him from its investigation and then concluded everything was fine.

The day after the plant manager had done his own koshering of the line, it caught fire, Horowitz alleges, “because there was chametz residue remaining in the ovens.” Nevertheless, Horowitz says, Manischewitz shipped that line’s macaroons, with OU’s kosher for Passover seal, and OU neither issued a recall or a public alert.

In the suit, Horowitz also says that after 18 years of supervising the silos from where the Passover flour was shipped, that duty was stripped from him. And after receiving one particular 40,000-pound delivery of flour, he had to reject it because the containers the flour was shipped in were wet, a clear Passover violation because once flour and water mix, it must enter the oven after no more than 18 minutes.

“I was being kept in the dark,” Horowitz told the Journal. “I was the guy for 20 years, totally in charge of the entire operation. I was the arbiter. If I didn’t know about something, then there’s something very wrong, because I was hired to be in charge. I’m the one that’s expected to say that it’s kosher.”

Horowitz left the Manischewitz plant in December and has not done kashrut work since. He’s suing the OU and Manischewitz for, among other things, defamation and infliction of emotional distress, which he said resulted in him having to take medical leave, the specifics of which are “stress related.” He’s still employed by the OU but said it stopped paying him one week after he left, and recently stopped paying for his medical insurance.

“[There is] no question that that stress relates to all of the aggravation that I felt that I had to fix what was broken and needed to be addressed,” Horowitz said. When asked why he filed the suit just before Passover, Horowitz said it was his last resort after many attempts of trying to resolve his concerns without going the legal route.

“I filed this complaint with great sadness,” Horowitz said. “I have gone way beyond the call of duty trying to get their attention, begging them to address these issues — they and the Manischewitz company. I only went forward with this lawsuit when people that I sent to intercede told me you’re wasting your time.”

Horowitz said he had hoped that those people, who he said are prominent and reputable but that neither he nor his attorney, Arnold Pedowitz, would name, could help resolve Horowitz’s objections to OU’s and Manischewitz’s kashrut standards at the Newark plant.

He declined to answer whether there are any specific Manischewitz products he won’t eat this year for Passover, but said that when he left in December, the degree of the problems in the possible kashrut status of Manischewitz products “was exceedingly severe.”

“To tell you that I know that the things on your plate are no good, I can’t tell you that,” Horowitz said, adding, though, that he also “can’t tell you it is good” since he’s no longer there to supervise.

“The only way I can keep that job is I have a certain amount of certainty that that thing is good. I didn’t have that certainty,” Horowitz said. “I could not in good conscience go into Passover knowing there are people who would look at products and say, ‘If Horowitz says it’s fine, then that’s good enough for me.’ ”