Comer to subpoena USSS director for July 22 hearing

The big picture: Republican chairmen of committees with jurisdiction over federal law enforcement are growing increasingly frustrated with repeated failed attempts to lock down briefings for their members, sources familiar with the matter told Axios.

• Both the Oversight panel and the Homeland Security Committee had scheduled member briefings for Tuesday that had to be postponed because DHS officials would not confirm a briefing time, the sources said.
• Cheatle is expected to appear at the July 22 hearing, the Oversight spokesperson said, and the U.S. Secret Service did not immediately respond to a request for comment.
• Comer, Homeland Security Committee Chairman Mark Green and Intelligence Committee Chair Mike Turner (R-Ohio) are each leading branches of the investigation.

Zoom in: The FBI and DHS are considering holding a briefing call Wednesday with all House members, a source familiar with he matter told Axios.

The bottom line: The shooting has touched off a bipartisan flurry of congressional scrutiny into security for presidential candidates.

• Republicans have asserted they will use all tools at their disposal to gather information as part of the various investigations.

Go deeper: Secret Service questioned on security shortcomings at Trump rally