WASHINGTON — A congressional ethics watchdog has concluded there is “substantial reason to believe” that the wife of Pennsylvania Rep. Mike Kelly used nonpublic information gained through her husband’s position in Congress to purchase stock last year, a likely violation of federal law and House rules.

A report from the Office of Congressional Ethics released late Thursday detailed the April 2020 purchase of stock in an Ohio steelmaker. The company had threatened to shut down a plant in Mr. Kelly’s district unless the Trump administration took action that would help make it more competitive, steps the administration took after Mr. Kelly, a Republican, and others intervened.

The ethics office has recommended that subpoenas be issued for Mr. Kelly, his wife, Victoria, a senior staffer and former Commerce Secretary Wilbur Ross because they declined to be interviewed or participate in the investigation.

“Victoria Kelly made an uncharacteristic stock purchase ... on April 29, 2020, and profited from this purchase. The purchase occurred just after her husband, in the course of his official job duties, learned confidential information about the company,” the report states.

Though the ethics office investigates complaints, only the House Ethics Committee has the power to punish a lawmaker for wrongdoing. The committee said in a statement that it would review the report and investigate further.