People in Chicago continue to brace for the potential deployment of the National Guard on city streets, after President Trump on Tuesday repeated his threat to send in troops to fight crime, even as data shows crime is already trending down in the city over the past year.

The president said on Tuesday he still plans to send National Guard troops to Chicago, after the city saw at least 8 people killed and 51 others wounded over the Labor Day weekend.

"Well, we're going in. I didn't say when. We're going in," Trump said. "Look, I have an obligation. This isn't a political thing. I have an obligation."

The president's comments came after a federal judge in California ruled that the Trump administration violated federal law earlier this year when it deployed federal troops in Los Angeles earlier this summer in response to protests against U.S. Immigration and Customs Enforcement.

The president said the judge who issued that ruling was a "radical left judge," and noted the ruling does not require him to withdraw 300 troops who remain in place in Los Angeles, although he did not mention that the ruling expressly prohibits them from performing any law enforcement functions – including making arrests; performing seizures; or providing traffic, crowd, or riot control.

Earlier Tuesday, some military veterans in Chicago spoke out against President Trump's threats while some Republican state lawmakers from outside the city backed the president.

A military veterans' group rallied at Federal Plaza in the Loop on Tuesday morning, urging current National Guard members to refuse participation in what they call an illegal deployment, but a group of conservative Illinois lawmakers – most of them from downstate – said they want troops on Chicago's streets.

"We need to make substantive change," Illinois state Rep. Martin McLaughlin (R-Barrington Hills) said.

McLaughlin and other members of the Illinois Freedom Caucus, comprised of some of the most conservative Republicans in the state legislature – none of whom represent the city of Chicago – voiced support for the deployment of National Guard troops in Chicago to address crime.

"To me, it is a public safety issue that can be addressed. It has been addressed successfully in D.C. Let's bring it to Illinois," McLaughlin said, referring to the president's deployment of National Guard troops in Washington.

While a CBS News analysis found crime has dropped in D.C. since President Trump deployed troops and federal law enforcement agents there, local police data was already showing that reported crimes were trending downward in Washington prior to the president's action.

In Chicago, crime statistics compiled by the CBS News Chicago data team show the city has made significant progress in the most violent categories over the past year, with the number of homicide victims down 31%, shootings down 36%, and overall violent crime down 21%.

At Federal Plaza, groups in opposition to a National Guard deployment in Chicago encouraged active-duty troops to not carry out what they say are illegal orders.

"To members of the National Guard: you are not alone. If you are questioning your orders, if you have concerns about your orders, you are not alone. You have options. You have rights. You have the right and the duty to refuse illegal orders," said Aaron Hughes, an Iraq war veteran with About Face: Veterans Against the War.

"Service members signed up to uphold the Constitution. Service members did not sign up to become pawns for a president trying to score political points against the opposing party," attorney Brad Thomson said.

They also want Gov. JB Pritzker to take more steps to oppose the potential deployment as commander in chief of the Illinois National Guard.

"Back up your words with actions by directing the Illinois National Guard not to report; to refuse these orders," said Daniel Lakemacher, a U.S. Navy veteran with About Face: Veterans Against the War.

Guard members can face disciplinary consequences for refusing orders or deployment.

Groups opposing troop deployment in Chicago said they plan on protesting in Federal Plaza if the president follows through on his threat to send the National Guard to Chicago streets.