Demonstrators marched through Seattle Thursday during a protest called "Nobody Is Above The Law." The nationwide protests are centered around protecting the Robert Mueller investigation after President Trump fired Jeff Sessions as Attorney General.

A crowd gathered at Cal Anderson Park on Capitol Hill around 5 p.m. for a rally, attended by Gov. Jay Inslee, Rep. Pramila Jayapal, and King Co. Executive Dow Constantine. Then the group marched toward the federal building at 915 2nd Ave.

Protests were planned in at least 900 cities nationwide, aimed at protecting Special Counsel Robert Mueller's investigation into Russian interference in the 2016 presidential election. The mobilization comes after President Donald Trump fired Attorney General Jeff Sessions Wednesday, replacing him with a man who has previously criticized the probe and offered suggestions on how to slow it down.

At the rally, Rep. Jayapal said the protests are a warning shot that Trump should not interfere with Mueller.

"It's telling the President - and Republicans that need to step up right now - to show that this is bipartisan - that we will not stand for this, we need to make sure that no president is above the law, and that this investigation continues, and that we get the answers, transparency, and accountability that the American people deserve."

She added that when Democrats take control of the House in January, she plans to push for further investigation into Trump's actions.

RELATED: Democrats win House: So what happens next?

The protest left Cal Anderson Park after the rally. Marchers, escorted by police, filled downtown streets during the evening commute before the crowd gathered in front of the federal building around 6:30 p.m. for more speeches.

Katherine Cleland marched at the front, shouting chants into a megaphone.

"This is amazing, just wonderful," she said. "It came together so fast."

She said she felt drawn to the event by a love of country and Democracy.

"And my hope for my kids' future," she said. And she hoped the sentiments carried to the White House.

"Tonight they better be hearing us, because we're the American people, and they need to listen to us," she said.

Others felt motived by fear.

Krystan Holzthum marched with her husband Nick. She used crutches, and he was in a wheelchair.

"Me and my husband, we're a minority," she said. "And so if he makes it unsafe for racial minorities, he's going to make it unsafe for us."

She grew emotional talking about why they came to march.

"They're trying to get rid of our healthcare, and if they do that, we're going to be put back in institutions and nursing homes," she said. "And that's not the life we want. We want to be part of American society and American life."

Additional protests were held around Western Washington Thursday, such as in North Bend and Edmonds.

The group Nobody Is Above The Law said on its website that Trump "crossed a red line."

Sessions resigned Wednesday -- indicating he did so at Trump's request -- and the President appointed Matthew Whitaker, Sessions' chief of staff, as the Acting Attorney General. The move superseded the regular order of succession which would have placed Deputy Attorney General Rod Rosenstein the Acting AG role.

Rosenstein has been overseeing the Mueller probe after Sessions recused himself from the investigation, but a Department of Justice spokeswoman said Whitaker would be "in charge of all matters under the purview" of the DOJ.

MArch1_1541729725505.JPG

Critics worry Whitaker may be unlikely or unwilling to defend the investigation, given his history of partisanship and loyalty to Trump. Nobody Is Above The Law said it wants Whitaker to recuse himself from supervising the investigation.

"Trump putting himself above the law is a threat to our democracy, and we’ve got to get Congress to stop him," the group said on its website.

Protect Mueller protest
A Google map screenshot from the Nobody Is Above The Law website showing hundreds of planned protests for Nov. 8, 2018. The protests are meant to raise awareness to protect the investigation of Special Counsel Robert Mueller.
Pittman, Travis

Nobody Is Above The Law said it had been preparing "rapid response" protests, just in case of a major development in the investigation. According to its website, those developments include:

1. Firing Mueller

2. Pardoning key witnesses

3. Preventing the investigation from being conducted freely by firing Rosenstein or repealing regulations establishing the office.

4. If Mueller's findings show significant wrongdoing by Trump or if the findings are hidden from the public.

The group also urged people to pressure Congress to protect the Mueller investigation.

During a brief stint last year as a conservative legal commentator on CNN, Whitaker often appeared as a Trump defender, saying he saw no evidence the president colluded with Russians during the 2016 campaign or obstructed justice. He wrote last year on CNN.com that Deputy Attorney General Rod Rosenstein should limit the scope of Mueller's investigation to stop him from delving into Trump's finances.

"If he doesn't, then Mueller's investigation will eventually start to look like a political fishing expedition. This would not only be out of character for a respected figure like Mueller, but also could be damaging to the President of the United States and his family — and by extension, to the country," he wrote.

The change of leadership at the DOJ came one day after Democrats won control of the House of Representatives, meaning Trump will face more oversight than he has under the Republican-controlled Congress.