On the agenda: school safety, police training, social media, firearm safety, and mental health.
ABC13 reporter Pooja Lodhia is in Austin to cover the hearings Wednesday.
Steve McCraw, director of the Texas Department of Public Safety, testified, giving his first public statement on the shooting since late May when he cast blame at Uvalde schools police Chief Pete Arredondo for not giving orders sooner to breach the classrooms where the gunman was inside.
During the Senate Committee testimony, McCraw said law enforcement authorities had enough officers on the scene of the Uvalde school massacre to have stopped the gunman three minutes after he entered the building.
COMPLETE COVERAGE: Uvalde school shooting
Police officers with rifles instead stood and waited in a school hallway for more than an hour while the gunman carried out the attack.
Delays in the law enforcement response have become the focus of federal, state, and local investigations.
Eight minutes after the shooter entered the building, an officer reported that police had a "hooligan" crowbar that they could use to break down the classroom door, McGraw said. Nineteen minutes after the gunman entered, the first ballistic shield was brought into the building by police, the witness testified.
McCraw told the Senate Committee that Arredondo decided to put the lives of officers ahead of the lives of children.
The public safety chief began outlining for the committee a series of missed opportunities, communication breakdowns, and other mistakes.
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"It has been reported that he didn't have a radio with him. That's true. He did not," McCraw said of Arredondo.
McCraw also said the classroom door could not be locked from the inside.
In addition, McCraw said police and sheriff's radios did not work within the school. Only the radios of Border Patrol agents on the scene worked inside the school, and even they did not work perfectly.
DPS director lays out series of failures in response to shooting
Questions about the law enforcement response began days after the massacre. McCraw said three days after the shooting that Arredondo made "the wrong decision" when he chose not to storm the classroom for more than 70 minutes, even as trapped fourth graders inside two classrooms were desperately calling 911 for help and anguished parents outside the school urged officers to go inside.
Arredondo later said he didn't consider himself the person in charge and assumed someone else had taken control of the law enforcement response.
The 18-year-old gunman used an AR-15-style semi-automatic rifle.
Tuesday night, the Uvalde city council is slated to consider granting Arredondo a leave of absence. Arredondo is a new council member, who was sworn in after the massacre on May 24.
SEE MORE: Uvalde victims' parents call for police chief's resignation at emotional school board meeting
Arredondo testified for five hours at a private Texas House committee hearing. Houston police SWAT Sgt. Thomas Calabro is also set to testify.
Gov. Greg Abbott called on lawmakers to make legislative recommendations in response to the mass shooting.
The Senate Committee hearings, which started off with meetings Tuesday and and continue on Wednesday this week, are public.
WATCH: How law enforcement narrative of Uvalde mass shooting changed
How law enforcement narrative of Uvalde mass shooting changed
The Texas Tribune and the Associated Press contributed to this report.
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