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Newhall incident

SOLVED1970Valencia, California (Newhall area), near the site of the shootout on Interstate 53 SOURCESUPDATED JUL 2026

Documents violence · suicide — written to inform, not to shock.

Illustrative

On the night of April 5, 1970, CHP officers Walt Frago and Roger Gore stopped a vehicle occupied by Bobby Davis and Jack Twinning near Castaic, California, after the pair had been reported for a traffic altercation earlier that evening. The stop occurred in the parking lot of a coffee shop in Valencia. Davis and Twinning initially complied but then opened fire, fatally shooting Frago and Gore within moments of each other. Backup officers James Pence and George Alleyn arrived and exchanged gunfire with the two suspects, who retreated to their car for additional weapons before continuing the fight. Both Pence and Alleyn were fatally wounded during the exchange. A bystander, Gary Kness, attempted to intervene using a fallen officer's weapons but ran out of ammunition and took cover. A third patrol car arrived, and after a brief further exchange of gunfire, Davis and Twinning fled the scene separately.

Davis stole a nearby camper after pistol-whipping its owner, Daniel James Schwartz, and was arrested hours later by Los Angeles County Sheriff's deputies after the stolen vehicle was located. Twinning broke into a nearby house and took the occupant hostage. After the hostage was released and negotiations concluded, deputies used tear gas to enter the house; Twinning killed himself as officers entered on the morning of April 6.

In 1972, Davis was convicted and sentenced to death for the murders of the four officers. Following the U.S. Supreme Court's ruling in Furman v. Georgia, which invalidated existing state death penalty statutes, his sentence was commuted to life imprisonment without parole. Davis died by apparent suicide in his cell at Kern Valley State Prison in 2009.

The incident prompted extensive review of CHP training and procedure. Investigators identified contributing factors including the officers' inexperience, the decision to approach and search suspects before backup arrived, lack of body armor, unfamiliarity with issued shotguns, and difficulties reloading revolvers under fire without speedloaders. As a result, the CHP became the first major state police agency to adopt speedloaders, standardized ammunition training, and revised procedures for approaching high-risk stops. The department also ended the practice of collecting spent cartridge casings during range training, a change linked to observations from the scene.

In 2006, the California Legislature passed a resolution designating a stretch of Interstate 5 in Santa Clarita as a memorial highway named for the four slain officers, with a dedication ceremony held in 2008 attended by Kness.

Key facts

Victims
Walter Carroll Frago, George Michael Alleyn, James E. Pence Jr., Roger Davis Gore, Daniel James Schwartz
Date
1970
Location
Valencia, California (Newhall area), near the site of the shootout on Interstate 5
Case status
solved

Case timeline

  1. 1970-04-05

    CHP officers Walt Frago and Roger Gore stop a vehicle occupied by Bobby Davis and Jack Twinning in Valencia, California; a gunfight ensues in which Frago and Gore are killed.

  2. 1970-04-05

    Backup officers James Pence and George Alleyn arrive and engage the suspects; both are fatally wounded during the exchange.

  3. 1970-04-06

    Bobby Davis is arrested by Los Angeles County Sheriff's deputies after stealing a camper and pistol-whipping its owner.

  4. 1970-04-06

    Jack Twinning, after taking a hostage in a nearby house and releasing him, dies by suicide as deputies enter the house following a tear gas assault.

  5. 1972

    Bobby Davis is convicted and sentenced to death for the murders of the four CHP officers; his sentence is later commuted to life without parole following Furman v. Georgia.

  6. 2006-08-11

    California Senate Concurrent Resolution 93 designates a stretch of Interstate 5 as a memorial highway for the four slain officers.

  7. 2008

    A dedication ceremony for the memorial highway is held on the 38th anniversary of the incident, attended by Gary Kness.

  8. 2009-08-16

    Bobby Davis dies by apparent suicide at Kern Valley State Prison.

Best coverage

No approved coverage links are attached yet.

People

  • Walter Carroll Frago

    VICTIM

    CHP officer killed during the shootout, age 23

    citation on file

  • George Michael Alleyn

    VICTIM

    CHP officer killed during the shootout, age 24

    citation on file

  • Bobby Augusta Davis

    CONVICTED

    Convicted in 1972 and sentenced to death for the murders of the four CHP officers; sentence later commuted to life without parole; died by suicide in prison in 2009

    citation on file

  • James E. Pence Jr.

    VICTIM

    CHP officer killed during the shootout, age 24

    citation on file

  • Roger Davis Gore

    VICTIM

    CHP officer killed during the shootout, age 23

    citation on file

  • Daniel James Schwartz

    VICTIM

    Camper owner pistol-whipped by Bobby Davis; survived

    citation on file

  • Jack Wright Twinning

    CHARGED

    Suspect in the shootout; died by suicide on April 6, 1970, before any prosecution

    citation on file

Places

Valencia, California (Newhall area), near the site of the shootout on Interstate 5

34.4233, -118.5853

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Common questions

What happened to the victim?
On the night of April 5–6, 1970, two career criminals killed four California Highway Patrol officers in a gun battle outside a coffee shop in Valencia, California, in what was then the deadliest single day in California law enforcement history.
Where did the crime happen?
Valencia, California (Newhall area), near the site of the shootout on Interstate 5.
Who was convicted?
Bobby Augusta Davis (Convicted in 1972 and sentenced to death for the murders of the four CHP officers; sentence later commuted to life without parole; died by suicide in prison in 2009).
What is the current status of the case?
Status: solved. Last verified July 2026.

Sources

  1. Newhall incidentwikipedia · Wikipedia · 2026-07-07
  2. Contemporaneous coverage — chp.ca.govnews · chp.ca.gov · 2026-07-07
  3. Contemporaneous coverage — leginfo.ca.govnews · leginfo.ca.gov · 2026-07-07

Last verified JUL 2026

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