Scott, 19, is charged with 20 counts of attempted murder, The (New Orleans) Times-Picayune reported. Magistrate Judge Gerard Hansen set Scott's bail amount at $500,000 for each count.
Following the hearing, Scott went straight to another hearing on a previous gun and drug charge. There, Judge Arthur Hunter ordered Scott to be held without bail until Tuesday, when the court with reconsider Scott's bail. Prosecutors in that case argued that Scott was a danger to society.
Scott was arrested Wednesday night in eastern New Orleans' Little Woods section after a three-day manhunt, police spokesman Garry Flot said.
Authorities did not say if a weapon was found.
Law-enforcement agents from a U.S. Marshals Service task force worked with New Orleans police special operations to take Scott into custody, WDSU-TV, New Orleans, reported.
Police say Scott opened fire into a crowd as the annual Mother's Day "second line" parade passed an intersection.
Second line is a New Orleans brass band parade tradition, where people not in the official parade, or "first line," follow the official band just to enjoy the music.
Ten men, seven women, a boy and a girl -- both 10 years old -- were struck in the hail of gunfire.
Three people remained hospitalized in stable to critical condition early Thursday. The other victims were treated and released, officials said.
Police said they identified Scott Monday after footage of the shooting was released.
The video shows a crowd at the parade suddenly running chaotically in all directions, with some people falling to the ground as a man in a white T-shirt and dark pants appears to be shooting a gun into the crowd. The man then turns and runs out of the picture.
The Seventh Ward neighborhood where the shooting occurred suffers from high gun-crime levels.
Sunday's shooting was the third holiday in New Orleans this year in which guns were fired into crowds, Mayor Mitch Landrieu said Monday.