Millions of Americans are casting mail ballots via drop boxes. Sen. Marco Rubio, R-Fla., said that’s dangerous.

"There’s danger involved in drop boxes," Rubio said in the Oct. 18 debate with his Democratic rival, U.S. Rep. Val Demings. "People need to think about it. OK. Imagine someone decides, ‘Oh, there’s a drop box. I’m just going to put some explosive and and blow it up and burn all of those ballots’ and now those votes don’t count at all.’"

We can’t predict the future, but we can look at the past. Rubio’s statement defies two decades of experience nationwide in millions of Americans safely using drop boxes. 

Rubio’s spokesperson pointed to an article about someone setting fire to a drop box in Los Angeles County in 2020. We also found reports about a drop box fire in Boston that same year. (In both cases, elections officials offered replacement ballots to affected voters.) 

Although it is possible for someone to try to explode a drop box, we found no evidence to suggest that the boxes are widespread targets of criminals. 

Dropping a ballot in a box "is just as secure as submitting a ballot during in-person voting," said Craig Latimer, supervisor of elections in Florida’s Hillsborough County.

Drop boxes were used for many years without controversy until President Donald Trump in 2020 cast doubt about their security. The boxes allow voters to bypass the post office; they are directly handled by local election offices. 

They are commonly used in states where generally all voting is by mail, including in Republican-led Utah. Oregon has used drop boxes for more than 20 years. In Washington state in 2020, about 72% of voters submitted their ballot via a drop box.

Rubio in 2020 touted the convenience of drop boxes.

Rubio told "Fox and Friends" that after finding a line at early voting, he ordered a mail ballot and planned to use a drop box. "You can drive right up to the voting site and show them your ID, you give it to them. They put it in a little drop box —  just like if you voted inside."

In 2022, the Republican-led Florida Legislature passed a law that renamed drop boxes "secure ballot intake stations."  Florida law generally requires that any such stations be placed at election offices or early voting sites, and must be monitored by staff who empty them daily. A law passed in 2019 also had rules for secure ballot drop boxes.

We interviewed elections officials in Miami-Dade, Broward, Hillsborough, Pasco, Manatee and Lee counties, and none reported attacks on the boxes or intake stations. Because the boxes are monitored by people on site, "I think that would be a deterrent" to criminal activity, said Tommy Doyle, Lee County supervisor.

In Pinellas County, two election workers are stationed by the intake stations, and no ballots are left unattended at any point, said Dustin Chase, spokesperson for the county’s election supervisor. 

Drop boxes are wheeled inside to secure election offices at the end of the day, and those inside are locked up, officials said. Anything suspicious is reported to law enforcement.

Outdoor drop boxes are often made of heavy metal and bolted to the ground. They include locks, fire prevention measures and narrow openings to insert ballots. Many drop boxes are under surveillance by either staff or video. Election officials, often in bipartisan teams, frequently empty the drop boxes.

The Elections Group, which offers technical expertise to election officials, recommends that officials place drop boxes in secure locations and prepare law enforcement to respond to incidents.

"There are a number of steps local election officials take to secure drop boxes, but the safety of ballots also depends on citizens treating those boxes with respect, abiding by laws," said Jennifer Morrell, a partner at the group and former election official in Colorado and Utah.

One of the best security measures for voters who cast mail ballots — via a drop box or mailbox — is to track those ballots. Many jurisdictions allow voters to sign up for a text or email tracking service that alerts them when their ballots are received and accepted for counting.

Paul Gronke, an expert on early voting at Reed College, said "one of the big advantages of voting by mail is that the ballot can be tracked and if it never arrives at an elections office, the voter can cast a replacement ballot."

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