CHICAGO (CBS) — Four members of Congress from the Chicago area have blasted the Chicago Bears for backing a new league policy requiring players to stand during the national anthem if they are on the field.

In a letter to Bears owner Virginia McCaskey and chairman George McCaskey, Representatives Robin Kelly, Jan Schakowsky, Bobby Rush, and Danny Davis suggested the NFL is violating the players’ right to speak out on issues of racial injustice and police brutality.

“It is disappointing that your franchise voted to silence the players you employ, during this important national dialogue,” the letter stated. “The only way that the city of Chicago, our state, and this nation can move beyond this problem is by engaging in a constructive, respectful, representative discourse that helps communities heal by acknowledging injustices and listening to one another’s voice. This is not the time to silence the aggrieved.”

Former 49ers players Colin Kaepernick and Eric Reid were the first NFL players to kneel during the anthem in 2016 to protest police brutality against African Americans. The NFL protest movement grew in 2017, prompting President Donald Trump and other conservatives to accuse players of disrespecting the flag and the military.

The lawmakers’ letter to the Bears comes on the same day the Super Bowl champion Philadelphia Eagles were supposed to have visited the White House. However, President Donald Trump canceled that visit, blaming a dispute over the national anthem.

“They disagree with their president because he insists that they proudly stand for the National Anthem, hand on heart, in honor of the great men and women of our military and the people of our country,” the president said in a statement.

Pres Trump cancels @eagles event Tuesday because of players dispute over taking a knee during National Anthem. So announces different event for invited fans: pic.twitter.com/zN31XwWjGZ — Mark Knoller (@markknoller) June 4, 2018

However, not a single Eagles player kneeled during the anthem at any game last season.

The Eagles posted a statement in response saying they are “grateful for all of the support we have received and we are looking forward to continuing our preparations for the 2018 season”:

In their letter to the Bears, the four members of Congress from Illinois defended players who have knelt during the anthem.

“Players who kneel silently in no way hamper the ability of the game to be played, nor do they diminish stadium security, business operations, or quality of gameplay,” they wrote. “The issue of police brutality and inequality for all people of color is the reason that NFL players are using their Constitutional right to free speech and peaceful protest to address this concern.”

Last month, the NFL announced a new policy that will require all players and personnel that are on the field during the anthem to stand while the anthem is played. However, the league also removed a rule requiring players to be on the field for the anthem, allowing them to stay in the locker room when the anthem is played on the field.

The new policy would allow the league to fine teams whenever players or other personnel on the field do not stand for the anthem. Individual teams can also impose their own fines or other punishments for players or personnel who do not stand.

While the league originally announced the new policy was unanimously approved by team owners, according to published reports the owners did not hold a formal vote. Instead, team executives held an unofficial poll of owners.

In their letter to the Bears, the members of Congress asked if the McCaskeys knew about the vote.

“Did you vote to affirm this policy, did you abstain, or were you not present at the meeting?” they wrote.

The letter also demanded to know how the Bears plan to implement the policy at the team level, and whether players will have any input in crafting that policy.

Noting that 68 percent of Bears players are black, the members of Congress suggested the Bears risk alienating a large portion of fans.

“You benefit from the support of so many fans of color who share player concerns on the issue of police brutality. One can argue that there is a time for protest, or that we should keep politics out of football, but did your ownership take into account the politics that inspired, and the social impact that would result from this new anthem policy?” they wrote.