WASHINGTON — American military officials at the Guantánamo Bay prison recently hardened their approach to hunger-striking prisoners, detainees have told their lawyers, and are allowing protesters to physically deteriorate beyond a point that previously prompted medical intervention to force-feed them.

The claim comes during two significant developments for the military commissions at Guantánamo this week, including a Supreme Court decision on Tuesday not to hear an appeal in a much-watched case. Together, the events are renewing attention on the wartime prison operation that President George W. Bush opened in 2002, that President Barack Obama tried without success to close and that President Trump has so far left alone.

Of the 41 men remaining at the prison, 10 were charged or convicted in the commissions system and the rest are being held in indefinite wartime detention without trial. That group includes about five men who have gone on hunger strikes to protest, detainee lawyers say.

For years, the military has forcibly fed chronic protesters when their weight dropped too much. Detainees who refuse to drink a nutritional supplement have been strapped into a restraint chair and had the supplement poured through their noses and into their stomachs via nasogastric tubes.