He likened HIV-specific statutes to those that would single out individuals based on gender, sexual orientation, genetic makeup or skin color. "It is inherently discriminatory to create different laws for different groups of people," he said.

Burris and Strub point to cases where heavier sentences were imposed on individuals with the virus — which, they argue, heightens fear and discourages others from getting tested. In one common scenario, they said, a couple breaks up, and one partner threatens to file charges against the other who is HIV-positive.

In a July study conducted by the SERO Project, 2,000 people living with HIV were interviewed, and nearly half said it was reasonable to put off testing to avoid potential prosecution. The study also found that a quarter of those interviewed knew others who were reluctant to get tested for the virus due to the same concerns.

Although law enforcement officials around the country continue to bring charges related to HIV transmission, the federal government has recommended shifting away from such policies.

Two years ago, President Barack Obama announced a new National HIV/AIDS Strategy that recommended against HIV criminalization.

"While we understand the intent behind such laws, they may not have the desired effect and they may make people less willing to disclose their status by making people feel at even greater risk of discrimination," the report said.

The report also noted advances in medical treatment. "HIV medications can extend the length and quality of life for infected individuals, and lower the amount of the virus circulating in a person's body, thereby reducing their risk of transmitting HIV to others," the report said.

The Centers For Disease Control and Prevention, meanwhile, advises that "State legislatures should consider reviewing HIV-specific criminal statutes to ensure that they are consistent with current knowledge of HIV transmission and support public health approaches to preventing and treating HIV."

California Rep. Barbara Lee, a Democrat, last year proposed the first piece of legislation to require states to repeal such laws; it did not pass.

But as the federal government has suggested re-evaluating such laws, bills were proposed in the last Maryland General Assembly session to toughen state laws, making HIV transmission a felony instead of a misdemeanor, and calling for a 25-year sentence.

Sen. Norman R. Stone Jr., a Baltimore County Democrat, and Del. C.T. Wilson, a Charles County Democrat, were the bills' lead sponsors. Neither Stone nor Wilson returned calls for comment.

The ACLU of Maryland testified against the proposal. In a statement, the ACLU wrote, "Increasing the HIV specific disclosure law in Maryland to a felony is wildly out of proportion to the possible harm, and is in bizarre and direct conflict with the direction of public health, human rights, and the substantially decreased consequences of HIV disease in the last 15 years."

Instead of sentencing to prison those who might spread the virus, policies should focus on encouraging the public to protect themselves and get tested, Burris said. "Punishing people who don't tell doesn't make sense."

