New York City May Day Rally

A member of an anarchist collective marches down Broadway with thousands of others on International Workers Day, or Labor Day, march on May 1, 2013 in New York City. The annual global gathering of activists, leftists and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Spencer Platt/Getty Images)

New York City May Day Rally

Thousands of people march down Broadway on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Spencer Platt/Getty Images)

New York City May Day Rally

Thousands of people march down Broadway on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Spencer Platt/Getty Images)

New York City May Day Rally

Thousands of people march down Broadway on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Spencer Platt/Getty Images)

New York City May Day Rally

Thousands of people march down Broadway on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Spencer Platt/Getty Images)

New York City May Day Rally

Thousands of people march down Broadway on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Spencer Platt/Getty Images)

New York City May Day Rally

Thousands of people march down Broadway on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Spencer Platt/Getty Images)

New York City May Day Rally

Thousands of people march down Broadway on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Spencer Platt/Getty Images)

New York City May Day Rally

Thousands of people march down Broadway on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Spencer Platt/Getty Images)

New York City May Day Rally

Thousands of people march down Broadway on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Spencer Platt/Getty Images)

New York City May Day Rally

Thousands of people march down Broadway on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Spencer Platt/Getty Images)

New York City May Day Rally

A demonstrator takes part in a May Day demonstration in New York, May 1, 2013. Union workers, immigrant rights activists and Occupy Wall Street supporters staged a rally and a march to celebrate May Day. (Credit: EMMANUEL DUNAND/AFP/Getty Images)

New York City May Day Rally

Demonstrators take part in a May Day demonstration in New York, May 1, 2013. Union workers, immigrant rights activists and Occupy Wall Street supporters staged a rally and a march to celebrate May Day. (Credit: EMMANUEL DUNAND/AFP/Getty Images)

New York City May Day Rally

Demonstrators take part in a May Day demonstration in New York, May 1, 2013. Union workers, immigrant rights activists and Occupy Wall Street supporters staged a rally and a march to celebrate May Day. (Credit: EMMANUEL DUNAND/AFP/Getty Images)

New York City May Day Rally

Demonstrators take part in a May Day demonstration in New York, May 1, 2013. Union workers, immigrant rights activists and Occupy Wall Street supporters staged a rally and a march to celebrate May Day. (Credit: EMMANUEL DUNAND/AFP/Getty Images)

New York City May Day Rally

Demonstrators take part in a May Day demonstration in New York, May 1, 2013. Union workers, immigrant rights activists and Occupy Wall Street supporters staged a rally and a march to celebrate May Day. (Credit: EMMANUEL DUNAND/AFP/Getty Images)

New York City May Day Rally

Demonstrators take part in a May Day demonstration in New York, May 1, 2013. Union workers, immigrant rights activists and Occupy Wall Street supporters staged a rally and a march to celebrate May Day. (Credit: EMMANUEL DUNAND/AFP/Getty Images)

New York City May Day Rally

Demonstrators take part in a May Day demonstration in New York, May 1, 2013. Union workers, immigrant rights activists and Occupy Wall Street supporters staged a rally and a march to celebrate May Day. (Credit: EMMANUEL DUNAND/AFP/Getty Images)

New York City May Day Rally

Demonstrators take part in a May Day demonstration in New York, May 1, 2013. Union workers, immigrant rights activists and Occupy Wall Street supporters staged a rally and a march to celebrate May Day. (Credit: EMMANUEL DUNAND/AFP/Getty Images)

New York City May Day Rally

People run down Broadway in Manhattan on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual May Day global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Photo by Mario Tama/Getty Images)

New York City May Day Rally

People run down Broadway in Manhattan on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual May Day global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Photo by Mario Tama/Getty Images)

New York City May Day Rally

People run down Broadway in Manhattan on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual May Day global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Photo by Mario Tama/Getty Images)

New York City May Day Rally

A man yells during protests on Broadway in Manhattan on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual May Day global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Mario Tama/Getty Images)

New York City May Day Rally

People run down Broadway in Manhattan on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual May Day global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Photo by Mario Tama/Getty Images)

New York City May Day Rally

People run down Broadway in Manhattan on International Workers Day, or Labor Day, on May 1, 2013 in New York City. The annual May Day global gathering of immigration rights activists, leftists, labor unions and others often results in confrontations with police. The very first Labor Day in America took place on May 1, 1886, as a celebration of the American labor movement and the adoption of the 8-hour work day. (Credit: Mario Tama/Getty Images)