Amtrak is considering allowing people to store guns in lockboxes on most of its trains, which critics say would weaken security measures that instead should be strengthened in light of the shooting at last weekend's White House Correspondents' Association dinner.

The company has been considering the policy change since at least early this year, after being pressured by Trump administration officials to ease restrictions on transporting weapons, two people familiar with the proposed plan told The Associated Press on condition of anonymity because they weren't authorized to speak about it publicly.

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They said the railroad hasn't abandoned the proposal despite Saturday's arrest of a man who authorities say traveled by Amtrak from California to Washington, D.C., with his firearms intent on killing President Donald Trump and other administration officials at Saturday's event.

Cole Tomas Allen was arrested after authorities say he tried to race past security barricades near the hotel ballroom that was hosting the dinner, prompting an exchange of gunfire with Secret Service agents. A Secret Service officer wearing a bullet-resistant vest was shot in the vest and survived.

Authorities say Allen was armed with a shotgun and semiautomatic pistol that he brought with him by rail from his home in Torrance, California. Amtrak declined to say if he followed the company's existing rules, which would have required him to declare he had guns and allow the railroad to lock them up with his checked bags. A lawyer for Allen has said he has no criminal record and is presumed innocent.

Amtrak's proposed rule change, which the railroad could begin testing soon, calls for adding lockboxes to its trains to allow passengers throughout the country to bring guns aboard, instead of only allowing guns on trains that have locked baggage cars, according to the people who spoke to the AP.

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The change would open up more than 1,500 trains a day to allowing guns aboard — including the routes that roughly 750,000 people travel every day in Amtrak's Northeast Corridor — instead of the current rule that only allows guns on a couple dozen mostly long-distance trains that have locked baggage cars.

John Feinblatt, president of the advocacy group Everytown for Gun Safety, said doing this would decrease safety.

"Just days after a man took an Amtrak train to Washington with a shotgun and pistol and tried to assassinate the president and other federal officials, the Trump Administration is trying to open the floodgates for firearms on every Amtrak route, while also moving to hollow out the agency responsible for enforcing gun laws and preventing gun trafficking," he said. "This will only make Americans less safe and Congress must step in before the next tragedy."

Officials at Amtrak and the Transportation Department didn't immediately respond to questions about the gun policy.

How this would change the rules

Currently, Amtrak requires passengers to declare they are bringing firearms aboard and secure them unloaded in a hard case. The guns must meet certain size and weight requirements. Such weapons are only allowed in checked baggage, similar to policies for firearms being transported on commercial flights.

This proposed change would still require guns to be locked up aboard trains, and only the conductor would have the key, according to the two people who spoke to the AP. But the plan would be to add lock boxes to every train.

It's unclear how Amtrak would determine who is legally allowed to carry a gun and whether local laws at their destinations would permit it. In some places, including New York City, there are restrictions on who can carry guns and a permit might be required. But other places have looser gun restrictions.

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Despite Amtrak's current gun policies, it's possible that some passengers are already armed or have carried guns on board. Unlike airports, which screen passengers and their luggage, train passengers aren't screened and Amtrak doesn't run passenger names through a criminal database to identify possible threats. That's true at crowded terminals such as Washington's Union Station and the tiny unstaffed stations throughout the country where trains stop in the middle of the night to pick up passengers.

In those sleepy unstaffed stations, passengers routinely board and the train starts moving again before the conductor ever makes contact or scans their tickets. So there would be at least several minutes before a gun could be secured under the proposal.

Security expert Sheldon Jacobson, whose research contributed to the design of the TSA PreCheck system used in aviation, said railroads should do more to screen their passengers ahead of time by collecting more information when they sell the tickets and checking passengers' backgrounds. But he said it's not possible to eliminate guns on trains when there is no way to enforce the rule.

"The initial condition is that there's almost 400 million guns in this country," he said. "Then work from there as opposed to trying to create a utopian environment where there's not guns and we're going to keep it that way."

Rail travel poses fewer risks than air travel, so it wouldn't be worth the investment needed to create a strict passenger screening system at every train station similar to what TSA does at airports, Jacobson said. But he acknowledged that calculation could change if there ever were a major tragedy on a passenger train.

"You have to weigh the risks and rewards. And you have to say, where are we going to put our money to get the greatest risk reduction for the greatest benefit with the least inconvenience to people?" he said.

Unions have sought worker protections for years

Unions have been fighting to strengthen passenger rail workers' protections for nearly a decade, after several incidents like the 2017 shooting of a conductor by an enraged passenger at the train station in Naperville, Illinois.

Two bills in Congress would give rail workers similar protections to what airline crews have by making it a federal crime to interfere with or assault a rail worker performing their duties. The unions have also had some success getting states to pass laws.

Amtrak and many other ground transportation companies barred weapons on trains and buses after 9/11, but none put security measures in place to detect or screen every passenger for firearms. In 2010, Congress passed a law requiring Amtrak and other companies to allow firearms to be transported as long as they are checked.