The many groups that have gathered on New York's noisy streets to engage in peaceful protest have long had a champion in Bill de Blasio, but now that the progressive is running City Hall, the honeymoon may be over.

“You would expect something like that from someone in government who didn’t profess to be for peaceful protests.”

- Civil liberties attorney Norman Siegel

Last week, aides to the mayor created a “free speech zone” so that a very small group of protesters wouldn’t mar a photo-op reopening a Queens boardwalk destroyed by Hurricane Sandy, DNAInfo reported. The move prompted a letter of protest from a group representing New York journalists and led one prominent civil liberties attorney to accuse de Blasio of hypocrisy.

“For someone who professes to be a progressive and believes in the right to peaceful protest, to then turn the First Amendment on its head when there are protestors who want to exercise their First Amendment to criticize you and your administration is extremely troubling,” attorney Norman Siegel told FoxNews.com Friday.

De Blasio aides said the zone was created so those who might be carrying signs wouldn’t block the view of others.

But Siegel said corralling anti-de Blasio protestors in a pen 50 yards from an event was clearly unconstitutional and worthy of a legal fight.

He said one group has contacted him about acting as plaintiff in such a lawsuit.

“You would expect something like that from someone in government who didn’t profess to be for peaceful protests,” Siegel said.

De Blasio seemed to love peaceful protests before he became mayor.

Siegel said that years ago, de Blasio was a member of the New York City Council when he was arrested for protesting the closing of several Brooklyn firehouses.

As a candidate for mayor in 2013 de Blasio was arrested during a protest against the losing of a Brooklyn hospital.

When a grand jury refused to indict a cop in the choke-hold death of Eric Garner, de Blasio encouraged angry New Yorkers to exercise their First Amendment rights to engage in nov-violent protest over the decision.

Over the years courts have been called on to resolve free speech zone disputes involving the UN and special events like the Democratic and Republican conventions. In those cases, judges have sought to craft rulings centered on the issue of safety.

In the Rockaways on May 22, law enforcement officer and civic activist Philip McManus was banished to the special zone when he showed up in suit to protest with a sign urging more city funds for his community.

“I knew there was a place for me, but when I realized how far way it was, I said, ‘This is BS,’” he told DNAInfo.

The New York Press Club told de Blasio that penning protestors at a mayoral event was “outrageous.”

“To call an area restricted from access by the public ‘a free speech zone’ makes a mockery of our basic rights,” said the letter signed by the group’s president Larry Seary and legendary New York newsman Gabe Pressman, chairman of the Freedom of Press Committee.

A de Blasio spokeswoman told FoxNews.com only people with signs that would have blocked the audience were asked to move.

“The goal is to accommodate protests on site but also have smooth events in which participants can speak, guests can hear the program, reporters can ask questions,” she said.

The Associated Press contributed to this report.