Ms. Schutz, who first exhibited the painting last year in a gallery in Berlin, has stated that she intends never to sell the work. In a statement on Tuesday, Ms. Schutz said: “I don’t know what it is like to be black in America but I do know what it is like to be a mother. Emmett was Mamie Till’s only son. The thought of anything happening to your child is beyond comprehension. Their pain is your pain. My engagement with this image was through empathy with his mother.” She added: “Art can be a space for empathy, a vehicle for connection. I don’t believe that people can ever really know what it is like to be someone else (I will never know the fear that black parents may have) but neither are we all completely unknowable.”

The curators said that they wanted to include the painting because many of the exhibition’s artists focus on violence — racial, economic, cultural — and they felt that the work raised important questions, especially now, in a political climate in which race, power and privilege have become ever more urgent issues.

“For us it was so much about an issue that extends across race,” said Mr. Lew, who along with his co-curator, Ms. Locks, met with Mr. Bright on Tuesday to discuss his protest. “Yes, it’s mostly black men who are being killed, but in a larger sense this is an American problem.”

Ms. Locks said: “Right now I think there are a lot of sensitivities not just to race but to questions of identities in general. We welcome these responses. We invited these conversations intentionally in the way that we thought about the show.” She added that she felt the painting was a means of “not letting Till’s death be forgotten, as Mamie, his mother so wanted.”

The story of Till’s murder has begun to resonate loudly again in recent months. News recently emerged that the Mississippi woman who said that the 14-year-old Till whistled at her and was verbally and physically aggressive — an account that led to Till’s abduction, torture and killing — told a historian in 2007 that she had made up the most sensational part of her account.

The Black Lives Matter movement and greater awareness of the killing of black men by the police have led to efforts to film the Till story, with at least three screen adaptations in production.