Police spokeswoman Robin Snyder said police underestimated the number of marchers who would turn out Sunday, expecting perhaps a few thousand. "We weren't expecting the crowd that we got," she said.
Altogether, about 45 uniformed officers and a handful of Utah Highway Patrol troopers provided security along the march route between the Salt Lake City-County Building and the Capitol.
Near the Capitol, a group of illegal-immigration foes led by Utah Minuteman Project Chairman Alex Segura yelled "No Amnesty" and waved flags and signs protesting the march.
About a dozen officers in riot gear helped keep the two groups separated, but it was the 50 to 100 Latino volunteers that made the difference in that instance, Snyder said.
"They were great," she said. "They lined up to keep people out of traffic. . . . Even if someone started arguing they would jump right in."
Dressed in black T-shirts, the volunteers kept the marchers moving, picked up water bottles and other litter and used whistles to disperse heated arguments.
At one point several of the volunteers held hands to make a chain between the two opposing groups after a marcher lost control while "exuberantly" waving an American flag too near the protesters, Platt said. The man's flag was confiscated, but he was allowed to rejoin the marchers.
A pedestrian walking near the City-County Building at about 5 p.m. did hit a female illegal-immigration foe in the back of the head several times after claiming someone spit on her. No charges were filed.
Several heated verbal altercations took place throughout the day, but were squashed before nasty words turned physical. There were no arrests.
"They were peaceful," Snyder said. "No problems."
Earlier in the day Segura and Tony Yapias, director of the Proyecto Latino de Utah and a rally organizer, helped quell a verbal altercation that broke out. The two men had met Saturday and had promised to conduct peaceful rallies, Segura said.