Iowa’s Republican secretary of state has issued instructions saying counties can’t set up drop boxes to accept early ballots for this year’s general election, despite not challenging their use in more than a third of Iowa’s counties during previous elections.

The Iowa Secretary of State’s Office told county auditors during a recent series of training sessions that Iowa law does not allow the use of drop boxes for ballots, the Des Moines Register reported.

“This was a decision made years ago by the Iowa Legislature, not the Secretary of State’s Office,” wrote Kevin Hall, a spokesman for Secretary of State Paul Pate, in an email to the Register. “Nothing in the Iowa code has changed regarding this law.”

However, county auditors can set up a no-contact delivery system for voters in their office to use during regular business hours, Hall said.

Scott County Auditor Roxanna Moritz, who is also president of the Iowa State Association of County Auditors, said 39 of Iowa’s 99 counties have indicated they have already used a drop box system to collect ballots.

“During the primary, individuals did use drop boxes and nothing was said,” Moritz said.

The Trump administration has openly sought to undermine mail-in voting this fall, leading some election officials around the country to turn to ballot drop boxes in libraries, community centers and other public places as a way to bypass the Postal Service. But election officials in some states — mainly Republican-led ones — have opposed adding drop boxes, saying to do so would be too costly, raise security concerns or violate state laws.

Some county officials, including the auditor in Montgomery County, plan to use the drop boxes despite the secretary of state’s instruction.

Linn County Auditor Joel Miller, who used a drop box during the June primary, said he has set up drop boxes outside the county’s public services building and outside three local Hy-Vee stores for the November election.

The Linn County Board of Supervisors planned to vote Wednesday on whether to designate the drop boxes as “county-provided accessories of the Linn County Auditor’s Office.”

Hall said the Iowa Attorney General’s Office provided the Secretary of State’s Office with written clarification on what the law allows regarding absentee ballots but declined to release the document. The attorney general’s office also declined to release the document.

Gary Dickey, a Des Moines attorney who has represented groups that sued the secretary of state over Iowa’s election laws, disagrees with the legal interpretation that would forbid the use of drop boxes.

“The law allows a voter to have a designee return the ballot to the auditor’s office, and there is nothing that precludes the voter from making the auditor that designee,” “Dickey said.