SPRINGFIELD, Ill. — The Illinois Supreme Court rejected appeals Friday from two men who say their child pornography convictions should be thrown out because prosecutors didn’t prove the pictures showed real children instead of computer-generated images.

The cases raised questions about whether juries can still believe what they see in an era of Photoshop and computer gimmickry.

They also asked the justices to consider how the law should adapt to quickly changing technology.

The U.S. Supreme Court has said pictures must show actual children for child pornography to be illegal. Richard Dvorak, attorney for one of the defendants, argued it’s impossible to know whether that’s the case with pictures of unidentified children circulating over the Internet.

Advertisement “There’s no way a jury could just look at these images and tell if they’re real or not real,” Dvorak said.

The court disagreed, ruling that judges and juries can still decide for themselves.

One case involved Rudy Phillips, a Kankakee man who was arrested after a computer technician found pornography on his machine when he brought it to a store for repairs. The other defendant was Ernest Normand of Byron. He had sexual photos of his underage girlfriend, and police also found computer disks with sexual images of children.

On appeal, both men argued that the U.S. Supreme Court rulings on child pornography required prosecutors to prove the images showed abuse of real children.

But the Illinois court held that there is little chance of a defendant possessing computer-generated images that would fool viewers.

“We find little or no reason to fear that realistic virtual child pornography exists and was so readily available as to create an unacceptable risk that the trial judge, unaided by expert testimony, mistook legal computer-generated images for illegal child pornography,” Justice Rita Garman wrote in the opinion for People v. Phillips.

At least one computer expert said technology is advanced enough to make fake photographs appear real.

Victor Cortez, a graphic designer at the University of Illinois at Urbana-Champaign, said it would be a simple matter for someone to make a realistic-looking pornographic image. They could, for instance, take an innocent shot of a baby playing in the bathtub and alter it to include sexual material.

“That kind of technology has been around for years,” he said.

Cortez said it would be more difficult to create an entirely original image of a child in the way that characters are created from thin air in “Star Wars” movies. The image would probably be “too perfect” and easy to spot as a fake – although the technology is improving.

The defense attorneys argued realistic fakes are likely to be more common in the future. If the court doesn’t take that into consideration now, at some point, people will possess images that aren’t illegal and have to prove their innocence, they said.

Going after people for possessing child pornography even when the source of the image is in doubt shifts the burden of proof from the state to the accused, Dvorak argued.

“What it amounts to is punishing people for their thoughts, not their actions,” he said.

Dvorak said prosecutors should charge suspected child pornography collectors for attempting to possess the illicit material, because in those cases it wouldn’t matter whether the images were real or not.