Short answer: Because you should be. However, here's a better, longer answer because it isn't just cut-and-dry.
Let me give you a little perspective regarding where I'm coming from.
Having graduated college with my bachelor's degree in photojournalism and having experienced resistance from some subjects I've photographed, I'm a huge advocate for people knowing what they're getting into when they show themselves in public. Although there is no specific law in place, freedom of speech and of the press determines that anyone in the public's "plain view" is fair game when it comes to making pictures of them; no consent from the subject required. This protects the public by allowing photographers to disseminate important images. This includes law enforcement when acting in public spaces, homes (as long as the photographer is on the public sidewalk and not the grass, which counts as private property) and, of course, public protests, as a few examples.
I recently won a Michigan Press Association Collegiate Newspaper Division One award for a column I wrote on photojournalists' rights when photographing in public. You can basically understand the column's tone with this phrase I chose to conclude the piece: "If you wouldn't want someone you care about to see it, don't do it. If you decide to do it anyway, don't get mad at the photographer who decides your antics are newsworthy." For anyone who wants to learn more about the topic, the full column may be found here.
I'm writing this piece because it took me some time to understand why protesters are asking for their identities to be withheld. I'm writing because it took me some time to understand that my interpretation of professional duty and law, along with this sort of "restriction" on photography in public can coexist; in fact, they can't ethically exist without one another. Now, I feel it's my duty to share this information with my fellow hard-headed creators - photographic artists and photojournalists alike.
I'll focus on a press perspective first, but don't skip this portion if you're a photographic artist. Some of the following portions will be referenced when I talk about us later.
The public has a right to know what's going on. It's the responsibility of the press to report things of interest to the people of the United States. We are the watchdogs of politicians. We report on emergencies. We create images that marry the writing of our peers to help the public further visualize and understand what's happening in the world around them. We focus on faces because faces are the most emotive and communicative visual marker humans possess.
However, sometimes, these images can be used in opportunistic and violent ways.
I'd like to extend a content warning for violence to anyone reading past this point.
In this 2019 article published in The Chicago Tribune, Associated Press journalist Jim Salter reports on the deaths of six prominent protesters and activists who were photographed during the Ferguson protests in 2014. The piece also touches on the experiences of then-community activist Cori Bush, who, after her involvement in the protests, "[Has had her car run off the road,] her home has been vandalized, and in 2014 someone shot a bullet into her car, narrowly missing her daughter, who was 13 at the time."
Three of the aforementioned deaths were ruled suicides, but the mother of Danye Jones upholds her statement that her son was lynched. He was found hanging from a tree.
The topic was revisited by Politifact journalists Madlin Mekelburg and Samantha Putterman in an article published by the Austin American-Statesman June 5, 2020. As of the article's publication, no progress has been made in any victim's case.
Unsurprisingly, there has been a fair amount of speculation surrounding these homicides. Whether the victims were murdered in incidents unrelated to their involvement to the protests, by vigilantes or by more organized means still has yet to come to light.
Content warning lifted
Avoiding photographing faces in our work as photojournalists is hard; eyes are the window to the soul. How are we supposed to showcase the emotion and passion for these events if we can't capture what a face communicates?
It is our moral responsibility to learn how. Create images that don't include tattoos. Create images that focus on body language, hand shape, a mouth (and just a mouth) shouting. Show the absolute horde of people supporting the cause with a low angle that captures disembodied shoes walking by.
Take, for example, the image below:
An attendee raises her fist in solidarity during a rally against police brutality, June 13 at Rosa Parks Circle in Grand Rapids.
Part of the story is still being told. Her identity is protected. She has the freedom to protest safely and you have the freedom to document in accordance to the right given to you by law while avoiding her identifying physical characteristics.
Of course, this doesn't apply to subjects you have received explicit permission from to identify in your images, but as experienced photojournalists know, sometimes the moment - and the person - passes in the blink of an eye. Collecting required information from the subject just isn't possible at times. Use your best judgement.
If you're still not convinced you have a responsibility to create images without including the faces of protesters, remember the National Press Photography Association's Code of Ethics includes this point:
"Give special consideration to vulnerable subjects and compassion to victims of crime or tragedy."
For photographic artists who are covering protests as a way to document and support the cause, I understand you are not bound to the NPPA's code of ethics. However, you should be bound by your own code of ethics. The chances may be low that an individual you photographed ends up harmed because your photo identified them, but you shouldn't be comfortable with those chances. Your artistic, documentary, whatever, choice you use as an excuse to show a protester's face could lead to that person's death. Grapple with the thought of what kind of person would be comfortable with knowing they have the power to stop a murder and not take precautions to prevent it.
Additionally, photographic artists have more options when it comes to protecting protesters' identities in post-production. Photojournalists can't manipulate images under the NPPA code. Artists have free reign to do whatever they want in whatever media they use.
If you want to document through an artistic lens, photograph at protests freely, but take special consideration in post-production to blur faces. Make sure to blur tattoos as well, or crop them out of your framing all together. You can even choose to blur by using a unique brush tool to cover protesters' faces and identifying characteristics.
Again, an example is below:
Protesters chant during a march standing in solidarity with victims of police brutality June 13 in downtown Grand Rapids.
The context comes through, the size of the march is understood, the setting is apparent and emotion is communicated. This took me maybe thirty seconds to manipulate in Photoshop. It really is that easy.
There is no excuse for not participating in protecting the identities of these individuals, especially if you are profiting off of these images. Additionally, whether you're profiting off your protest images or not, if you aren't taking these precautions, I urge you to reflect on how your decisions are supporting the system of white supremacy in the United States, no matter the color of your skin. Keep in mind these protests are happening because Breonna Taylor, George Floyd, Elijah McClain and countless others who have been victims of police brutality.
Side note before I continue on: For those looking for more information, this link provides scientific analysis of police violence while this link provides a timeline of Black deaths at the hands of the police that have been heavily covered by mass media. Note that just because these acts of violence gained the most coverage, they aren't the only ones that have occurred.
By putting your perspective of how an image should look ahead of the safety of protesters, you are saying your benefit - whether it's social media clout, a paycheck or an addition to your portfolio - is worth endangering more lives. This reduces the amount of people at protests. This increases arrests against people of color. This increases violence against people of color. This makes it safer for white people to be centered in the movement. This upholds white supremacy and makes you complicit in it.
If you haven't been protecting the people supporting this movement already, you have no excuse to not do so now.