Yes, incarcerated firefighters is the term commonly used. I would hope that you would have as much of an issue with the practice as you do with the terminology.
From Fighting Wildfires to Digging Graves, Incarcerated Workers Face Danger on the Job
Incarcerated people comprise 30 percent of all wildland firefighting crews in California. The firefighters job is to clear areas surrounding a wildfire using chainsaws and hand tools, such as axes and rakes, to starve the fire of fuel. The work is as dangerous as it sounds; compared to other firefighters, incarcerated people fighting wildfires are four times more likely to sustain physical injurieslike cuts, bruises, dislocations, and fracturesand eight times more likely to suffer from the effects of smoke inhalation.
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While incarcerated California firefighters choose to work, many other incarcerated workers are not allowed a choice at all. The 13th Amendment ended slavery in the United States, but a loophole allows people convicted of crimes to be forced to work. In some states, prison officials can force people in their custody to work for nothing. Yet, even in states that do offer pay, like California, the wages offered are often shockingly low. Each year, states extract an estimated $11 billion in goods and services from the labor of incarcerated people who are paid little or nothing, often in unsafe conditions. Sixty-four percent of people working behind bars say that they fear for their safety, and 70 percent say they have not received formal training.
Incarcerated firefighters have some of the highest rates of injury among all prison workers, but they are far from the only people in prisons working incredibly dangerous jobs for meager pay.
https://www.vera.org/news/from-fighting-wildfires-to-digging-graves-incarcerated-workers-face-danger-on-the-job