Former Yale nephrologist Rex Mahnensmith MED ’77 is counter-suing the seven plaintiffs who filed a February federal lawsuit against him for sexual assault and sex discrimination.

Mahnensmith is also suing the clinic in which the alleged harassment took place. Six women and one man filed lawsuits against Mahnensmith, Yale University and DVA Renal Healthcare, Inc. — a subsidiary of DaVita HealthCare Partners, Inc. — alleging Title VII and Title XI violations. Mahnensmith, who was the medical director of the DaVita New Haven Dialysis Clinic and the Acute Hemodialysis Clinic in New Haven before retiring in April, filed 15 cross-claims against DaVita last month. These claims included allegations of negligence in their investigation, breach of contract and unfair trade practices. Mahnensmith also filed counterclaims against the original plaintiffs for defamation and emotional distress.

“It is not Dr. Mahnensmith’s contention that the plaintiffs and DaVita consciously conspired with one another to destroy his reputation and career. The individual plaintiffs each [have] his or her own reason for falsely charging him with misconduct,” Mahnensmith’s lawyer Robert Mitchell wrote in the counterclaim.

According to the cross-claim, Mahnensmith believes DaVita disliked his prioritizing patient care over profit at the clinic. As a result, DaVita administrators Elizabeth Chiapperino and Keith Parmalee helped the plaintiffs fabricate a sexual harassment case against Mahnensmith to remove him from the clinic, the cross-claim alleged.

Skip Thurman, a spokesperson for DaVita, told the News the company strongly disagrees with Mahnensmith’s allegations.

“When Dr. Mahnensmith’s conduct was brought to our leadership’s attention, we acted swiftly in conducting a thorough investigation,” Thurman wrote in an email to the News. “We determined it was important for us to remove Mahnensmith as medical director. The safety and health of our patients and teammates is a primary focus.”

In the original lawsuit, the plaintiffs alleged that on two occasions, Mahnensmith thrust his pelvis in a sexual manner against the chair a female plaintiff was sitting in.

The male plaintiff offered Mahnensmith a seat, but he did not sit down, the original lawsuit said.

“Dr. Mahnensmith replied with a smirk, ‘I’m not finished yet,’ and continued to sexually gratify himself until announcing to the group that he was finished,” the complaint read.

But Mahnensmith denied these allegations in his counterclaim, stating that he was simply doing exercises to reduce the pain caused by his degenerative spine disease, right leg sciatica and osteoarthritis. Mahnensmith’s lawyer compared accusations lobbied against his client to events in “The Crucible,” a play about the Salem Witch Trials.

“[Mahnensmith] says he didn’t do it, they say he did,” Mitchell said. “Why people get together and do this, I don’t know, but hopefully we’ll find that out in the course of developing the facts behind the case.”

Other allegations, including claims Mahnensmith touched a female plaintiff inappropriately on other occasions, made sexual comments and created a hostile work environment were dismissed by Mahnensmith as fabrications or easily explainable misunderstandings. He described these allegations as examples of the “collective torment” he was subjected to by the plaintiffs and part of a larger plan to remove him as the director of the clinic.

Jennifer Zito, who represents six of the seven plaintiffs, denied all of Mahnensmith’s claims.

“Dr. Mahnensmith’s allegations against the individual plaintiffs I represent are baseless and incredulous,” Zito said in an email to the News. “The allegation that [seven] plaintiffs each individually, each for their own personal reasons, just fabricated accusations of sexual harassment defies common sense.”

The plaintiffs of the original lawsuit are also suing Yale for inadequately supervising Mahnensmith, alleging that the University’s failure to act appropriately in this case falls into a broader pattern of unresponsiveness in the face of sexual misconduct allegations against faculty members.

Yale spokeswoman Karen Peart declined to comment on the countersuit and whether Mahnensmith was under any supervision at the clinic. Peart said the University cannot discuss the lawsuit as it is currently in litigation and the details of Yale’s arrangement with DaVita are issues relevant to the suit.

Mahnensmith has been in full-time clinical practice and various teaching positions since 1984.