The Brief

There’s a term you’ve probably come across more than once while traveling around Southern California: SigAlert.

It’s one of the best ways to keep on top of traffic delays in near real-time, but they’re also a harbinger of stress. If a SigAlert is issued on your route, good luck getting to your destination on time. There could be a car stalled on the freeway, a car crash or any number of other problems shutting down lanes.

But do you know why they're called SigAlerts? They actually started out as a radio tool.

How did SigAlerts begin?

Before SigAlerts lived online in an interactive map, and were issued by the California Highway Patrol, they came from a specialized radio receiver that broadcast recorded messages.

In the early ‘50s, civil defense officials had been looking into how to make an alert system in case of an attack from the U.S.S.R., which became the brainchild of Loyd Sigmon, executive vice president at L.A.’s KMPC radio station.

The system was first officially tested in November 1954. In City Hall, officials pressed a red button that took KMPC off air and instead broadcast civil defense information to listeners. Think of it like a Cold War version of the emergency alert system — the idea was to get urgent updates out fast, like potential attacks or major flooding.

A number of Southern California broadcasters signed on to install the necessary equipment, including KNX. Devices were also installed at the offices of civil defense personnel to speed up the process.

Sigmon also thought of a more daily use for the system. He approached the L.A. Police Department with an idea: set up a process for police departments to call the station when major traffic jams occur. But that wasn't really feasible for officers to do every time.

It’s unclear how many times Sigmon customized devices to use the SigAlert system in different ways, but according to SigAlert researcher Harry Marnell, for the LAPD, he used a $600 shortwave receiver and tape-recording device that booted up with a special tone. The LAPD would receive details from other agencies and then press a button to record and send that special tone with the information to radio stations (like a high-stakes telephone game).

The system, which was put into widespread use in Greater L.A. on Labor Day 1955, was intended to tell the public about a range of concerns: major freeway tie-ups, smog alerts, fire, explosions, dense fog and “atomic” attacks.

Today, it’s just about major traffic delays. Relaying of emergency information lies with things like the emergency alert system. But Sigmon has gone down in history as pioneering a way for mass communication. He died in 2004 when he was 95.

How an early SigAlert caused traffic

Ironically, a SigAlert sort of created a big traffic jam.

In January 1956, a major train derailment happened — the Santa Fe train wreck — and an alert went out asking for any available doctors and nurses to respond. But so many people responded — including nosy onlookers — that it turned into an even bigger mess.

Priests, who were asked to come for spiritual help, were caught in traffic or turned away because of the amount of people driving over.

The derailment killed 30 people and injured 117. But the LAPD’s use of the SigAlert called into question exactly how effective (or ineffective) it was to broadcast such requests for help without a way to control the traffic build-up.

The L.A. Times put out an editorial days after the wreck that called out local authorities for poorly managing the emergency.

And while it praised how the SigAlert brought a swift medical response, the editorial board wrote that “nobody had the wit to stop” the onlookers on the highways.

How LAPD responds when someone is experiencing a mental or behavioral health crisis is getting a closer look. 

Last week, Mayor Karen Bass issued an executive directive ordering an independent review of the department’s response, including its policies, training and use of force. 

“There is a severe shortage of mental and behavioral health care, and too many people in crisis have nowhere to turn,” Mayor Bass said in a prepared statement. “People cycle between the streets, emergency rooms, and detention facilities, and too often come into contact with law enforcement.” 

The Los Angeles Board of Police Commissioners will need to retain an independent firm to conduct the audit and report back recommendations to the mayor’s office within six months. Bass said that the firm selected should be experts in constitutional policing and crisis response. 

The review will determine how officers identify people in crisis, including those with intellectual and physical disabilities, and people who are under the influence of illicit substances.

LAPD officers fatally shot more than 60 people between 2021 and 2025, according to the most recent data the department reported to the California Department of Justice. All of those deaths will be reviewed.

The audit will also look into how the department tracks repeat calls about a person who is in crisis or needs help. Yong Yang’s case is one example. Yang was fatally shot by police in 2024, after his parents attempted to get him help during a behavioral health crisis.

His parents previously told The LA Local about how Yong Yang had nonviolent encounters with police before the encounter that ended in his death. They question why officers failed to de-escalate the confrontation before he was shot.

They’ve continued to call for accountability, even after LAPD closed its investigation into his death. Under Bass’ new directive, his case is one that would be reviewed. 

The audit will evaluate:

• Use of force: Incidents over the last five years of uses of force and arrests that resulted in death or serious bodily injury to determine if the person was experiencing a behavioral health crisis or had an intellectual disability.
• De-escalation: Incidents over the last five years that did not result in death or serious bodily injury to determine how they were de-escalated.
• Repeat calls: The department’s procedures for keeping track of people involved in repeated calls to police, including those who have a disability.
• Training: The training officers receive about incidents with people experiencing behavioral crises.
• Less-lethal options: What less-lethal force options are available to officers.
• Custody and care: Uses of restraint and processes for medical treatment for people in police custody. 
• Officer wellness: Protocols for providing officers with mental health care after these confrontations.

Bass’ order comes about a month after the police department released graphic videos of men who died during police encounters. One video captured officers sitting on and restraining a handcuffed man for an extended period of time at a holding facility in the San Fernando Valley. The man, Jose Carlos Hoyos-Munoz, died soon after. 

“When an encounter results in death or serious injury, we must rigorously examine whether our policies, training, tactics, supervision, and accountability systems are sufficient,” Bass said after the videos were released.

The post Mayor Bass orders independent review of how LAPD responds to mental health crises appeared first on LA Local.

A new law will require local agencies to publicly disclose audio recordings and written records of 911 calls originating from privately run immigration detention facilities. The bill was prompted by CalMatters reporting on alleged sexual assaults at the Otay Mesa Detention Center.

Gov. Gavin Newsom signed Senate Bill 423, called the Detention Facility Transparency Act, on Tuesday. It was one of 21 immigration-related bills in a package his office announced the same day.

The law will require local agencies to turn over recordings and written records of 911 calls from privately run detention facilities, if a member of the public requests them. It includes an exception if an active investigation is underway and requires redacting the names of affected individuals.

“Well, it goes without saying, these past two years, Donald Trump has brought fear and has brought anxiety, disruption and stress to our immigrant communities,” Newsom said in a recorded video statement on his website.

“So, today, I sign a number of bills to strengthen transparency and to strengthen accountability and oversight over federal immigration enforcement and civil detention in our state,” the governor said.

State Sen. Lena Gonzalez, a Democrat from Long Beach, introduced SB 423 as state investigations and courts found serious gaps in essential medical care within the facilities. She said the aim was to stop private operators, and the agencies that work alongside them, from keeping what happens behind detention walls from the public's view.

In February, L.A. Taco reported that detainees inside Otay Mesa were throwing lotion bottles wrapped with notes about conditions inside over the wall of the facility to organizers standing outside.

“For 280 days we haven’t eaten a single piece of fruit, banana, apple, orange, or anything fresh," an Otay Mesa detainee wrote, the news outlet reported. "We are all in one big room with no doors or windows. We can’t see any grass or trees. We are all constantly sick.”

Gonzalez, who is chair of the Legislative Latino Caucus, said no person “should have to resort to throwing notes over the walls of a detention facility to have their needs met and their voices heard.”

Earlier this year, CalMatters sought information, including 911 audio records and other reports, about alleged serious incidents at detention facilities through a California Public Records Act request. While a San Diego County sheriff’s spokesperson said the agency was not investigating those cases, he said he was unable to turn over additional records because they were part of “a law enforcement investigation.”

“When journalists and reporters attempted to obtain records about reported incidents at these facilities through the Public Records Act, they faced severe pushback from law enforcement, citing vague investigatory records exemptions, despite there being no active investigation,” said Gonzalez.

Immigrant Defense Advocates and the First Amendment Coalition co-sponsored the bill.

“The governor has sent a powerful message: No more secrecy. SB 423 makes clear that 911 calls and related records about events in detention must be released upon request. This will shed more light on a notoriously opaque system, leading to stronger oversight and accountability,” Ginny LaRoe, Advocacy Director, First Amendment Coalition, said in a written statement.

Gonzalez’s bill was one of several detention oversight bills Newsom signed Tuesday. Others impose a new 25% tax on private detention facilities, expand health, safety and oversight requirements for the centers, and add to the state attorney general’s oversight role.

The new laws take effect Jan. 1.

This article was originally published on CalMatters and was republished under the Creative Commons Attribution-NonCommercial-NoDerivatives license.

Six Flags Magic Mountain is retiring its famous X2 roller coaster amid lawsuits alleging serious brain injury caused by the ride.

The Southern California theme park said Tuesday that it is permanently shuttering the ride after nearly 20 years. Six Flags recently settled a wrongful-death lawsuit from the family of a 22-year-old man who died after riding the coaster in 2022, and three more lawsuits alleging traumatic brain injuries were filed last week.

“While X2 consistently passed a multitude of safety tests, we have decided to close the ride because we believe it’s the right thing to do,” park President Brian Oerding said in an online announcement. “Ride safety is a cornerstone of our business, and when we see guest confidence affected, we take it seriously.”

The ride has been closed since the evening of July 12, after two women who rode the coaster less than a week apart both needed to be rushed to the hospital after they exited.

One of them, 25-year-old Naomi Greer-Wilkinson, collapsed shortly after the ride ended and was found to have massive brain bleeding inside the skull that required emergency brain surgery. She remains in a vegetative state in the hospital, unable to speak or move and dependent on a ventilator. Her family filed a lawsuit against Six Flags on her behalf.

Her attorneys said more than 100 people claimed they suffered brain injuries from the roller coaster in the past two years, and more lawsuits would be filed in the coming weeks.

According to the Six Flags Magic Mountain website, the X2 roller coaster reaches a top speed of 76 mph (122 kph) and has a total length of 3,610 feet (1,100 meters). The seats rotate 360 degrees “so your body will be flipping around the entire time,” and the ride features two “raven turns” — half loops that turn into sheer drops midway.

It debuted at the park in 2002 under the name X as the world’s first “fourth-dimension” roller coaster and reopened in 2008 as X2 with new trains and special effects. The uniqueness of the ride drew thrill-seekers from around the world and garnered a fervent fanbase.

The park settled a wrongful-death lawsuit filed by the family of Christopher Hawley, a 22-year-old who died the day after he rode X2. He was taken to the hospital after the ride with severe brain bleeding. The medical examiner’s office said his death was from blunt head trauma. The case was settled at the end of August, a few days before the trial was scheduled to start.