A mural of Michelle Obama in Chicago ignited controversy this week following allegations that it copies a work shared on Instagram without crediting or paying the original artist. The case exemplifies the dangers artists face when posting work online, where images can easily be taken and used in violation of the original creator’s rights.

Unveiled on Friday, the mural shows Obama as an Egyptian queen and is nearly identical to an image posted on social media by artist Gelila Mesfin last fall. To create that work, Mesfin drew on a photograph of the first lady by for the New York Times, carefully manipulating Schorr’s image with intricate digital brushstrokes and layers of color.

Mesfin’s work went viral, eventually finding its way to the screen of Chris Devins. The Chicago-based artist and urban planner had recently been contacted by a congressional staffer in Chicago with the idea of installing a large black and white mural of Michelle Obama on her former elementary school on the city’s South Side. To fund the mural, Devins began a GoFundMe campaign, which eventually raised nearly $12,000. But unable to secure permission from the school, he created the work on a privately owned building across the street. And instead of a black and white photograph of the first lady, Devins used Mesfin’s artwork.

While Mesfin says she is supportive of the mural’s inspirational message, she has remained unyielding in asserting that she should have been asked for permission and attributed. On Monday of this week, Devins stated that Mesfin “has no legal grounds to stand on for copyright infringement,” arguing that since her image is a manipulation of Schorr’s photograph it isn’t protected. He continued, “You can’t appropriate a bike then sue someone for riding it.” Devins has since walked back on these comments, crediting Mesfin and offering to pay what he likened to the fee attached to a Getty stock image (a dubious comparison).

While application of this “she stole it first” mentality would be convenient for Devins, copyright law is much more nuanced—and probably on Mesfin’s side. That’s because her work likely constitutes a “fair use” exception to copyright laws, while Devins’s mural does not. So while Mesfin’s work is indeed a manipulation of a copyrighted image, her derivative work is still protectable under the law. And Devins’s adaptation, which amounts to a thoughtfully placed reproduction, likely falls short of fair use.

As such, the legal effects and practical consequences of each adaptation are dramatically different.

There are four criteria which a court may consider in determining whether a reproduction amounts to a fair use of a copyrighted work. The four concepts are: 1) the purpose and character of the work—which looks at the transformation made; 2) the nature of the original work—which considers the protectability of the prior work; 3) amount and substantiality of the portion of the work used; and 4) effect on the market for the value of the copyrighted work.  The importance and sufficiency of each point is flexible, and no one factor is uniformly more significant than another; different cases can dictate that different points are focused on.

In considering whether Mesfin’s adaptation was a fair use of the original photo, a legal analysis would likely focus on the first two criteria. That is, whether her work changes the original work in such a way that adds something new and tangible to the original photo, and also if there are parts of the original photo that are not protected. On these two points, the scales are tipped in Mesfin’s favor.

Her use of Schorr’s photograph shines a new light on the image of Obama, and undoubtedly involved skill and creativity. And while Schorr’s image is copyrightable, its protectability is somewhat limited to the positioning and lighting of the photo, since Michelle Obama as a person cannot be copyrighted. In this respect, while Mesfin did use the entire photograph, one could argue that her work incorporated elements of Schorr’s work that are unprotectable under copyright. And the fact that Mesfin created a digital work with limited commercial impact is also likely to weigh in her favor.

In contrast, Devins’s mural use is less likely to be considered transformative. Substantively speaking, his changes to Mesfin’s work are minimal. For all practical purposes, he has simply reproduced a digital work in a physical space. Devins claims that he spent all of the funds raised by the GoFundMe, but it is unclear whether he took payment. Whether or not he garnered a commercial benefit from the placement of the mural may have an impact on his fair use defense, but it would not, on its own, compel the end result.

Given that Devins is an experienced muralist, it’s perplexing that something as basic as ensuring an artist’s permission would have fallen through the cracks. But with billions of images circulating online, determining a work’s true source can be difficult and the rules around reproduction murky. Although he originally saw the image in thumbnail form on Pinterest, we don’t know where exactly Devins obtained the full-sized image he adopted into the mural given how many times Mesfin’s work was reposted. And if Devins had simply shared the work to his own Instagram feed it would’ve likely gone unnoticed. Still, in creating the mural, Devins unfortunately, but perhaps unintentionally, crossed a very real legal line.