On Monday, the Southern Poverty Law Center filed an ethics complaint against Judge Wiggins, saying he had committed “a violation of bodily integrity.” The group also objected to the hearing beyond the matter of blood collection, calling the entire proceeding unconstitutional.

Payment-due hearings like this one are part of a new initiative by Alabama’s struggling courts to raise money by aggressively pursuing outstanding fines, restitution, court costs and lawyer fees. Many of those whose payments are sought in these hearings have been found at one point to be indigent, yet their financial situations often are not considered when they are summoned for outstanding payments.

Several people who were at the hearing on Sept. 17 said they were unsure whether they were being ordered to pay the entire amount due or their usual monthly payment, which many had already been paying on time, often for offenses dating back a decade or more.

Mr. Green, 43, who owes thousands of dollars in connection with two marijuana-related convictions — one from 1998 — said he had offered to pay as much as he could but had been led to believe that he had to give blood anyway.

“He told us we got to go there and give some blood or we go to jail,” Mr. Green said. He said he had willingly given blood before but, like others there on that day, did not want to be compelled to do so.

Ordering defendants to give blood used to be more commonplace, particularly during wartime, according to “Flesh and Blood,” a history of blood transfusions and organ transplantation by Susan Lederer, a professor of medical history now at the University of Wisconsin-Madison.

In the mid-20th century, judges in several places around the country, including Honolulu after the Pearl Harbor attack, ordered people convicted of traffic violations to give blood or offered blood donations as an alternative to a fine. More commonly, prisoners would receive cash incentives or reduced sentences for giving blood. (As late as 2008, a judge in Broward County, Fla., offered traffic offenders the choice of a fine, community service or a blood donation.)