RALEIGH, N.C. — A former Army captain serving life prison sentences for the 1970 murders of his pregnant wife and two young children at a North Carolina base wants to leave federal prison due to his deteriorating health during the coronavirus pandemic.

Lawyers for Jeffrey MacDonald are expected to make their case Thursday before a judge at the Raleigh courthouse. It’s the same place where the ex-physician was convicted in 1979 for the murders. Federal prosecutors oppose his release from a Maryland prison.

Attorneys for MacDonald, 77, wrote in court documents that their client’s illnesses — chronic kidney disease, skin cancer and high blood pressure among them — make him among those who are at the highest risk for severe illness of death, should he contract COVID-19.

The government’s lawyers have said MacDonald doesn’t qualify for compassionate release, and that he waived his last two opportunities for parole in 2020. U.S. attorneys also wrote that MacDonald’s refusal last week to take a COVID-19 vaccination means he can’t rely on the potential risks of the illness to justify his release.

Prosecutors said MacDonald used a knife and an ice pick to kill his wife and children at their house on Fort Bragg before stabbing himself with a scalpel. They said he donned surgical gloves and used his wife’s blood to write the word “PIG” over their bed to imitate that year’s Charles Manson murders.

MacDonald maintains he was wrongly convicted, pointing to “drug-crazed hippies” as the culprits.

It became known as the “Fatal Vision” case, the title of a true-crime book MacDonald had invited author Joe McGinniss to write to demonstrate his innocence. Instead, McGinniss became convinced of his guilt.