Transcript for Federal clashes with Portland protesters raises legal questions about use of force
Tonight, Portland thrown into chaos. Months of tensions boiling over as the white house deploys federal agents against protesters, but now standing between those agents and the protesters, a sea of mothers of the here's kayna Whitworth. Reporter: An unreal scene unfolding in Portland in the last72 hours. All that cheering is because the group of protesters are meeting with the moms who have marched here tonight. A group of moms standing arm in arm, their bodies on the line for black lives. Shields to a growing number of demonstrators being teargassed by federal authorities sent in by president trump and managed by homeland security. I'm ready to pull my officers out there if the violence stops. I want to find a peaceful solution, but we have to protect the federal property and law enforcement officers there. A man pulled into an unmarked van, symbols of the chaos and confusion now engulfing the city of roses, as protesters continue to clash with protest. Now federal agent being sent onto American streets. Using tear gas on properties protesters. Reporter: And whether the federal government should be there in the first place. It's the government miscasting protesters as criminals and trying to scare people from going out and protesting police brutality. Reporter: For more than 50 days protesters have marched in port land. There's been tear gas the majority of the nights. Reporter: Nearly every night, garrison Davis has documented the protests that erupted in his city in the wake of George Floyd's killing. He saw moments of hope and violence. Rocks, bottles, bricks, biohazards thrown at us. All kinds of weapons thrown at us and we still are showing great restraint. Reporter: And recently, a protester fighting for his life after being hit in the head with what authorities call a non-lethal round. I heard the impact, blood pouring out of his head. Reporter: Project isle fired by one of the officers. But many on the ground say all they've done is inflamed tensions. What we have on the federal side is unmarked vehicles driving into crowds, pulling people off streets without probable cause as far as I can tell, and the people who are engaging in those activities aren't even willing to identify who they are, and they don't wear insignia on their uniforms, that's a real threat to democracy, because ultimately, there's no accountability for that. Reporter: Daryl turner is the president of the Portland police association. Tell me about how your officers feel about the federal troops. I can't speak for everybody. They need to work in concert with our, the local police. And so right now that's not happening, and that concerns me. Reporter: You still believe that police officers can protect and serve and make a positive -- I do, I do. Reporter: The lack of cooperation with local authorities is one thing, but many say the federal authorities acted unlawfully. In this viral video, a protesters is grabbed off the street by federal agents and throwned into an unmarked van. He too was grabbed right off the streets. Van didn't say anything. It was unmarked. People in military gear jumped out. No statement of why they were stopping us. So I feared for my life and I ran, they eventually caught up with me and pulled me into the van. Reporter: Mark says he was searched for weapons. His beanie pulled over his eyes so he couldn't see. And at no point did these people in the van identify themselves to you. Correct. Reporter: Not verbally. You couldn't see it on their clothes or the van. Correct. Reporter: Moms supporting protesters like mark and the black lives matter movement. Raising alarms about use of force. And whether or not the federal government should be there in the first place. We protect our children and our city. I raised my children here. I want to see this city be respectful for all citizens. Reporter: This is a much larger crowd than we have seen here in Portland. In the 54th night of protest. In yellow, you are seeing the moms show up. Tonight in Orange, those are the Our whole goal is to be here to amplify black voices and use our privilege to protect black bodies and make sure that they are safe and everyone knows that black lives matter. Reporter: Kris David felt drawn to the front lines as I saw the video of the men in combat fatigues with no insignia. I was very concerned about that. If the federal government can do thrashings anybody can acquire used combat fatigues, go get a mini van and abduct people off the streets and we won't know if that's the federal government or just civilians playing dressup. Reporter: Did you ever think you would say something about that about the government? Reporter: He was hoping to have a dialog with federal agents. I took the oath to the constitution extremely seriously, and I wanted to ask them why they were no longer honoring their oath of office. What they were doing was blatantly unconstitutional. Reporter: Davis says he joined in with largely peaceful protesters. Early in the night there were no signs of federal agents anywhere. All of a sudden, a phalanx of eight to ten feds come rushing out of the courthouse and I started trying to talk to them. Why are you dishonoring your oath to the constitution. One of the officers leveled a semi-automatic weapon in my chest, and then another officer came and plowed into me and knocked me off balance. Then I plant myself right there. I'm going to stand my ground right there. Reporter: What happened next was caught on camera by a local reporter. Did you know who was attacking you? Who, I don't know who they are, still, I don't know what agent say they are from. They have no insignia. They have these weird codes, alpha numeric codes on a patch, no names, no agencies, no nothing. Reporter: Why do you think they attacked you. I wasn't a person. I was a target. The thing that struck me was there was no coherent strategy they were exercising to do crowd control. Reporter: David says he was treated by medics on scene and take tonight hospital. His arm is broken in two places. There was an allegation of excessive force. Reporter: We were told in part, based upon the circumstances the deputies believed that the force was necessary to protect themselves and others from physical harm. But the detention of protesters this past weekend in Portland has also alarmed civil rights users who say this is a misuse of federal authority by the president who has promised to dominate protesters. What we're seeing is an attempt to silence protesters who are out on the street to protest police brutality and the response we're seeing is still more brutality. Reporter: Portland mayor Ted wheeler has called for the removal of federal agents. Your presence is not needed, it is not wanted. It is ratcheting up violence and vandalism. We need you to leave right now before somebody dies. Reporter: But the president has defended the action of the agents and on Monday threatened to send more to other cities. I'm going to do something. That I can tell you. Reporter: But mayors are pushing back, signing a letter demanding an immediate removal of federal officers and accusing president trump of using terror If we see this happening across different cities and watch the escalation from federal agents getting deployed, I think it will only prove the fact that what's going on here is an escalation rather than an attempt to bring law and order or to quote-unquote help local and state authorities. Reporter: After months of unrest, these clashs in Portland seem far from over. But for those now at the center of the conflict, there's still hope where the movement will go I want to use my 15 minutes to put out a message to my fellow vets. I also want to use my 15 minutes to try to refocus this whole discussion back on black lives Hope for resolution there. Our thanks to kayna. One on one with a top
This transcript has been automatically generated and may not be 100% accurate.