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Police escorts, sealed containers and chain of custody documentation: These are some of the measures that Pennsylvania counties take to secure ballots while they are transported from polling places to county facilities after polls close on Election Day.

The exact protocols vary by county. For instance, in Berks County, poll workers will transport ballots in sealed boxes back to the county elections office, where they will be locked in a secure room, according to Stephanie Nojiri, assistant director of elections for the county located east of Harrisburg.

In Philadelphia, local law enforcement plays a direct role in gathering ballots from polling places.

“Philadelphia police officers will travel to polling places across the city after the polls close and collect those ballots to be transported back to our headquarters at the end of the night,” said Philadelphia City Commissioner Seth Bluestein, who serves on the board that oversees elections in the city. “Each precinct is given a large canvas bag, and the containers that hold the ballots are placed into that bag and transported by the police.”

After polls close in Allegheny County, which includes Pittsburgh, poll workers will transport ballots in locked, sealed bags to regional reporting centers, where the election results are recorded, said David Voye, division manager of the county’s elections division.

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From there, county police escort the ballots to a warehouse where they are stored in locked cages that are on 24-hour surveillance.

Poll workers and county election officials also utilize chain of custody paperwork to document the transfer of ballots as they are moved from polling places to secure county facilities.

For instance, in Allegheny County, chain of custody forms are used to verify how many used and unused ballots poll workers are returning to county officials, Voye said. Officials also check the seals on the bags used to transport the ballots to confirm that they are still intact.

There are similar security procedures for counties that use ballot drop boxes to collect mail and absentee ballots. In Berks County, sheriff’s deputies monitor the county’s three drop boxes during the day, according to Nojiri. When county elections officials come to empty the drop boxes, which are secured by four locks, they unlock two of the locks, while the sheriff’s deputies unlock the other two.

Officials remove the ballots, count them, record the number of ballots on a custody sheet, and put the ballots in a sealed box before they transported back to the county’s processing center.

“There’s all kinds of different custody sheets and all that, again, is reconciled in the days after the election,” Nojiri said.

Philadelphia has 34 ballot drop boxes, which are emptied daily and twice on Election Day by election workers, according to Bluestein. The bags used for transporting ballots from drop boxes are also sealed, and workers who are returning these ballots complete and sign a chain of custody form.

“The transportation of ballots is done in a secure, controlled manner, and the public should have confidence in the integrity of that ballot collection process,” Bluestein said.

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This story is part of an explanatory series focused on Pennsylvania elections produced collaboratively by WITF in Harrisburg and The Associated Press.

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