The emergence of the Pre-Exposure Prophylaxis (PrEP) drug Truvada in 2012 was a real game changer—primarily, but by no means exclusively, for men who have sex with men. When taken regularly by HIV-negative individuals, it is highly effective at preventing transmission of the virus.

And yet, at least one insurance company, Mutual of Omaha, has decided to penalize people who take Truvada by refusing them long-term care insurance. An ongoing lawsuit, Doe v. Mutual of Omaha, seeks to change that.

John Doe, an unidentified gay man from Massachusetts, sought long-term care insurance from Mutual of Omaha in 2014. Long-term care insurance is complementary to regular health insurance: It provides coverage, including things like assistance with daily activities, for long-term illnesses or chronic medical conditions. In order to obtain long-term care insurance, applicants must generally undergo an underwriting process, where their risk of needing long-term care services in the future is assessed. In this instance, that involved checking Doe’s medical records and prescriptions. Once Mutual of Omaha found out Doe was taking Truvada, his application was denied, solely on that basis.

After being denied, Doe filed a complaint with the Massachusetts Commission Against Discrimination. That case is now being litigated in a Massachusetts federal district court. Both sides have filed for summary judgment, requesting that the judge rule in their favor without going to trial. The brief filed by Doe’s attorneys, GLBTQ Legal Advocates & Defenders (GLAD) helps illuminate why Mutual of Omaha’s position in this case is so mistaken.

The denial wasn’t really about Doe in particular. Mutual of Omaha has a blanket policy of refusing long-term care insurance to anyone who takes Truvada, regardless of sexual orientation. But Doe argues that this policy disproportionately affects gay men—making it a “disparate impact” case. A disparate impact occurs when an otherwise neutral policy—in this case, denying long-term care insurance to all PrEP users—disproportionately affects members of a protected class. The Massachusetts Public Accommodation Law prohibits discrimination in public accommodation based on sexual orientation. Because Mutual markets and sells long-term care insurance to everyone in Massachusetts, it falls under that law.

And experts on both sides of the lawsuit agree that gay men make up 80 percent of the people that use Truvada. That’s an undeniably disparate impact, even if Mutual denies insurance to straight people who take Truvada too.

However, proving that the policy disproportionately affects the class of which Doe is a member—gay men—is only the first step. Mutual could keep their policy, even with the disparate impact, if it proves to the court that the policy is necessary to achieve a “valid interest.” The company doesn’t really manage that, even though it tries a multitude of reasons. Its stated goal is that it would like to keep the number of HIV-positive people in their long-term care insurance pool low. Setting aside the fact that such a stance is problematic, the company has not shown how its policy of denying Truvada users coverage will help it achieve that goal.

First, Doe points out that Mutual doesn’t ask people, during the underwriting process, about their risk factors for getting HIV. This means that people who are at a high risk for HIV, such as individuals who do not practice safer sex, could make it into the insurance pool relatively easily. In contrast, Mutual bars people who take Truvada, a drug designed to limit that person’s chances of acquiring the virus. It seems painfully obvious that the Truvada user has a lower, rather than a higher, risk of contracting HIV.

Mutual also tried to say that it had a valid interest in barring Truvada users because those users might not adhere to the regimen of taking PrEP regularly or being appropriately monitored by their physician. (PrEP regimens are most effective when taken daily). This is flawed in a few ways. First, such a problem isn’t peculiar to PrEP: Doe’s lawsuit notes that 75 percent of Americans have trouble taking medications as directed. Next, Mutual already has a policy in place to deal with this: it assesses whether people adhere to any medication regimens by looking at their medical records and other documentation. There’s no reason it couldn’t have checked with Doe’s doctor to be certain Doe was regularly taking Truvada. Mutual doesn’t have a blanket policy of denying users any other drug based solely on concerns about medication adherence. Therefore, that interest is likely to fail as well.

Lastly, Mutual tried to rely upon the fact that Truvada is a relatively new drug and the side effects are therefore less known. In theory, that’s not a terrible reason for a long-term care insurer to deny coverage. If a new drug ends up causing a side effect that itself requires long-term care, insurers want to avoid accepting people on those drugs. However, Mutual isn’t nearly as concerned about newer medications that are not PrEP. Doe’s lawsuit discusses other new medications that Mutual covers, all of which are new enough to lack an extensive record of claims experience or data on significant side effects. Indeed, some of those new drugs carry with them things like an increased risk of dementia or acute kidney injury, but Mutual does not maintain a policy of automatically excluding users of those drugs.

At root, what this case is really about is homophobia: a particularly virulent strain that relies upon the idea of gay men as sexually out of control, and assumes that PrEP users are only taking the drug so that they can be overly promiscuous. (Unfortunately, this is a view internalized by many in the gay community as well.) Mutual succumbed to this view and denied coverage to someone actively working to decrease his risk of contracting HIV. Worse, it has continued to fight this legal action for nearly three years, which speaks to a deep commitment to refusing to insure Truvada users.

And the insurer isn’t alone. A lawyer for GLAD told the New York Times in February they knew of 14 other instances where insurance providers denied some type of insurance to gay men on PrEP. When those companies do explain why they’re turning people down, they say that people on PrEP “must be engaging in high-risk sexual behavior,” according to the Times. And this sometimes extends to employers too: Until February of this year, Publix, a supermarket chain that employs more than 130,000 people in Florida alone, refused to cover PrEP in its workers’ health-care plans.

HIV-positive people and people at risk of contracting HIV fought long and hard to ensure access to health care and health insurance, and that is no less vital in the long-term care setting. They shouldn’t be derailed by homophobia that shames gay men for being sexual beings or for taking healthy steps to reduce their risks.

Hopefully, the federal court in Massachusetts will see this the same way and rule in favor of Doe. If it does, Mutual and other insurers in the state would not be allowed to deny someone long-term care insurance simply because they use Truvada.

Unfortunately, this is going to have to be fought court by court, state by state. But a win here would be a great start.