Judge Thomas Mulvahill of the Boulder County court made the orders today.
Appearing at a hearing in Boulder County court, Alissa affirmed that he understood his rights under the law and understood that he would be held without bail.
He faces 10 counts of murder and an attempted murder charge stemming from the rampage on Monday at the grocery store in Boulder, some 28 miles (45 km) northwest of Denver.
Prosecutors may file additional charges against him in the coming weeks, District Attorney Michael Dougherty told judge Mulvahill.
Defense lawyers for Alissa requested that the suspect undergo a full mental health assessment, which would likely push back his preliminary court hearing by a couple of months.
Alissa waived his right to a preliminary hearing within 35 days to allow time for that assessment.
“We cannot do anything until we are able to fully assess Mr. Alissa’s mental illness,” said Kathryn Herold, a defense attorney for Alissa.
Herold’s previous clients include a Colorado man who pleaded guilty to murdering his pregnant wife and two young daughters in 2018
Another public defender representing Alissa, Daniel King, defended the gunman who killed 12 people in a movie theatre in Aurora, Colorado, in 2012.
The bloodshed at King Soopers was the nation’s second mass shooting in less than a week, after a gunman fatally shot eight people at three Atlanta-area day spas on March 16.
The two attacks have reignited a national debate over gun rights and prompted President Joe Biden to call for new legislation from Congress.
A bill intended to impose stricter background checks and ban certain types of semi-automatic rifles has stalled amid Republican opposition.
On Monday afternoon, Alissa arrived at the grocery store carrying a handgun and wearing a tactical vest, according to an affidavit.
Six days earlier, he had purchased a Ruger AR-556 pistol, a weapon that resembles a semi-automatic rifle, the affidavit said.
The supermarket, still a closed-off crime scene, has turned into a memorial site, with people leaving flowers, candles and condolence messages outside. Boulder Mayor Sam Weaver told CNN on Thursday that the city was looking into creating a more permanent memorial nearby.
Among the victims were store employees, a grandfather-to-be and a Boulder policeman who was first on the scene.
The attacks terrorised the community and felt all too familiar in a state that has experienced some of the most shocking episodes of gun violence in U.S. history.
Darcey Lopez, a King Soopers employee who hid in a cabinet beneath the cheese-wrapping station in the store when the gunman opened fire on Monday, is still reeling from the horror she lived through.
“I still hear the gunshots in the store – it’s just something that kept playing over and over in my mind for about the first 24 hours. Now it’s at night. It’s really bad at night,” Lopez said.
