UPDATED 05/04/11 5:25 a.m.

CHICAGO (WBBM/CBS) — One hundred twenty-five years ago Wednesday, the Chicago Police Department suffered what it still considers its most devastating loss.

As WBBM Newsradio 780’s Nancy Harty reports he top brass of the Chicago Police Department gathered today to mark the 125th anniversary of the Haymarket Conflict.

LISTEN: Newsradio 780’s Nancy Harty Reports

Eight officers were killed and 59 wounded after someone threw a bomb at police trying to break up a crowd of striking workers in Haymarket Square.

That prompted police to fire shots. It’s not clear how many of the protesters returned fire or were killed themselves.

Descendants of the fallen officers gathered at Chicago Police Headquarters, 3510 S. Michigan Ave., holding yellow roses as they heard accounts of their relative’s injuries and deaths.

Geraldine Docekal, the great granddaughter of Mathias Degan, the first officer killed in the conflict, says the tribute means a lot to her family and helps them understand what happened.

Interim Police Supt. Terry Hillard ordered reinstatement of a tradition started by surviving officers where they placed a wreath at the foot of the Haymarket memorial statue, outside of headquarters.

That honor was carried on from 1886 until 1947, when the last survivor died.

Hillard added another wreath by laid in front of the case holding the stars of the fallen officers every May 4.

The events of the Haymarket affair go back to May 1, 1886, when crowds of people traveled to various workplaces urging a strike in favor of an eight-hour day – some everyday union laborers, others anarchist political activists. The rally picked up more and more participants as it picked up participants on May 3 and 4.

They clashed with police several times, and on May 3 at the McCormick Reaper Plant, two demonstrators were shot and killed by police who allegedly fired into the crowd.

The following day, a crowd gathered at Haymarket Square, at Des Plaines and Randolph streets. The gathering was initially peaceful, but as the crowd dwindled, someone threw a bomb at the police officers who had gathered at the scene, leaving eight officers dead and 60 injured. Police opened fire afterward, and chaos erupted.

It was never learned exactly who threw the bomb, but outrage erupted across the city and the nation. Newspapers editorialized about an anarchist conspiracy theory, and police took hundreds of people into custody. Thirty-one people were indicted, and eight stood trial – George Engel, Samuel Fielden, Adolph Fischer, Louis Lingg, Oscar Neebe, Albert Parsons, Michael Schwab and August Spies. All were anarchist labor activists.

The trial was widely criticized for being conducted without any evidence that the defendants were involved in the bomb throwing or in planning it, or even that there was any conspiracy among anarchists to attack police.

Nonetheless, all eight defendants were convicted, and seven were sentenced to death. Engel, Fischer, Parsons and Spies were all executed at Cook County Jail, while Lingg committed suicide. The others were imprisoned, until Gov. John Peter Altgeld pardoned them in 1893.

Despite the carnage, labor experts say the Haymarket Affair led to positive change for workers.

“The struggle at Haymarket was really the right to fight for the eight-hour day, the right to organize, the right to collective bargaining, the right to free speech, the right to peaceably assemble, and this went against the corporate interests of the day,” said Larry Spivak, president of the Illinois Labor History Society.

Spivak said recently that labor is engaged in a similar struggle today, as Wisconsin Gov. Scott Walker has succeeded in passing a law that strips unionized state employees of almost all their collective bargaining rights. The Wisconsin law is now being challenged in court, but similar laws were also approved in Indiana, Ohio and elsewhere.

The statue itself has been a subject of hostile acts several times. When it stood in the old Haymarket Square was destroyed in 1969 by a bomb blast for which the radical Weather Underground group claimed responsibility, and after being rebuilt and rededicated the following year, the group blew it up a second time.

The statue was later moved to the old Central Police Headquarters at 11th and State streets, then to the private courtyard of the Police Training Academy, before finally being relocated to the present-day police Headquarters.

Meanwhile, generations of activists after the Haymarket Affair decried the trial of those charged with the bombing is considered a miscarriage, and called those who were executed martyrs. Thus, the Haymarket Affair became the inspiration for the adoption of May 1 as a holiday commemorating laborers worldwide, which it has been since 1889.

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