On the last night of the Democratic National Convention in July, SEPTA Transit Police Officer Minjoo Kim and Sgt. Dave Parke took their places on a security line near Broad Street and Pattison Avenue and saw something they didn't like, but felt bound to protect.
Hundreds of demonstrators marched past the phalanx of officers outside the Wells Fargo Center, where the convention was being held.
They chanted. They sang. They yelled - sometimes at the officers.
Then, someone lit an American flag on fire.
The officers stood watch.
But once the crowd dispersed, Kim and Parke exercised some First Amendment rights of their own: They scooped up the remnants of the charred flag and turned them over to a supervisor at SEPTA's Market Street headquarters.
When it comes to burning the American flag, there's some confusion on the part of President-elect Donald Trump, who has proposed to punish flag burners.
But there was no confusion on the part of Officers Kim and Parke, who understand that the piece of cloth that represents the land of the free also includes the freedom to burn it.
"I understand it's their First Amendment right, I truly understand," said Parke, 46, an Army veteran. "But with me being a veteran, I just can't leave that behind like a piece of trash. It's not a piece of trash. It's our flag, our country's flag . . . and that means something to me."
The Stars and Stripes means something to Kim, too.
Kim was 10 when his parents left South Korea for opportunity in America.
"They believed in the freedom and equality promised to all people in this country," said Kim, who is 30. "And I, in turn, grew up with a great respect and love for this country."
Kim became a U.S. citizen in 2010.
The officers brought the flag to their supervisor, Capt. James Reynolds, who was impressed with their allegiance to the flag.
"You don't have to like [flag burning], but it's the law," he said. "They showed great respect for the citizens and for the job."
Reynolds showed the flag to SEPTA Police Chief Thomas Nestel, who promptly and proudly tweeted out the officers' actions.
"On Thursday night, citizens expressed their 1st Amendment Right by burning an American flag in front of police," he tweeted. "On Friday morning, Transit PO Kim & SGT Park collected every piece of the burned flag from the ground."
Reynolds made a mental note to do something with the flag, but then duty called and the manila envelope with the remains got lost under paperwork.
But recently, Reynolds came across the envelope and thought, "Oh, God, I want to do something with that."
A couple of hours of arts and crafts later - skills that got him a little ribbing from his colleagues - Reynolds created a shadow box with the remnants of the flag to commemorate the day and the officers' actions.
The officers were summoned to headquarters.
They were touched by the gesture, but made it clear when I recently caught up with them outside the Allegheny station on the Market-Frankford El that they hadn't done it for attention or kudos.
We didn't do anything special, they said.
These days, upholding democracy is the most special thing we can do.