The House Oversight and Accountability Committee launched a probe Tuesday into Vice President Harris’s efforts on the border, asking an agency largely outside her portfolio to turn over documents about her work on immigration.

In sending the request, committee Chair James Comer (R-Ky.) is seeking to elevate an issue Republicans hope will help them at the polls in November.

Harris was tapped by President Biden to manage the administration’s root causes strategy, an initiative aimed at investing heavily in development and democracy building throughout Latin America in the hopes of curbing immigration flows to the U.S.

Comer’s request asks U.S. Customs and Border Protection (CBP) to turn over any of its correspondence with Harris’s office. CBP is tasked with managing day-to-day operations at the border but has little role in addressing broader immigration goals in the region.

Some of the agencies most involved in the root causes strategy are the State Department, U.S. Agency for International Development (USAID), and the U.S. trade representative in addition to the Department of Homeland Security (DHS). While the State Department and USAID have numerous resources on the strategy referenced on its websites, the CBP website does not contain a single reference to the program.

In his letter to CBP, Comer said it’s “unclear what actions, if any, Vice President Harris has taken to fix the border crisis.”

He asks for all documents and communication with Harris’s office “related to the southwest border or illegal immigration.”

Though CBP plays little role in carrying out the root causes strategy, it does process migrants who arrive at the border and has vetted migrants from another initiative of the Biden administration that allows temporary entrance of citizens of Cuba, Haiti, Venezuela and Nicaragua if they’ve secured a U.S. based sponsor.

Comer’s office did not respond to a request for comment about why the committee sought information from CBP rather than other agencies connected with Harris’s portfolio.

But his letter notes her work on the strategy in addition to referring to her as a “border czar” — a term also used in the early days of the administration for Roberta Jacobson, who was officially the special assistant to the president and coordinator for the Southwest border.

“Vice President Harris focused on the purported ‘root causes of irregular migration’ from Central America. Central to Vice President Harris’s root causes initiative is an effort ‘to provide $4 billion to the region over four years.’ Vice President Harris has traveled to Central America—to Mexico and Guatemala in 2021 and to Honduras in 2022—more than she has traveled to our own southern border,” Comer wrote.

Comer’s letter is the latest effort by GOP lawmakers on the border, coming a day after House Judiciary Committee Chair Jim Jordan (R-Ohio) released his own report reviewing how “the Biden-Harris administration” has handled migrants on the terror watch list. 

Democrats have fought Republican efforts to blame them for the border, noting that the GOP tanked a bipartisan immigration deal after it came under criticism from former President Trump.

Biden in June implemented a policy restricting asylum and movement at the border, resulting in a drop in border crossings seen as comparable to Trump-era levels.

“In June, the Border Patrol recorded 83,536 encounters between ports of entry, the lowest number since January 2021, and below the number of encounters between ports of entry in June 2019, the last comparable year prior to the pandemic,” DHS said last month.