The way Dave Salkin tells it, he warned the tenants in his warehouse in Milwaukee's Riverwest neighborhood several times that they were exceeding their monthly $800 utility allotment. When their electric bill swelled to $1,400, Salkin couldn't pay it. The power was cut off.

Salkin didn't know at the time in 2012 his tenants were ATF agents running an undercover storefront aimed at getting illegal guns and drugs off the streets. And Salkin, who was not under investigation as part of the sting, didn't know — until Wednesday — that the federal agents later went behind his back, got his account information off his electric bill and then called We Energies pretending to be him. The information was contained in an ATF document obtained Wednesday by the Milwaukee Journal Sentinel that detailed findings of an internal investigation into the bungled sting.

"Account statements were improperly taken and information contained in one of those statements was improperly used to impersonate the landlord in a telephone conversation with the electric power provider," according to the report, prepared by the ATF's Office of Professional Responsibility and Security Operations. "That's crazy," Salkin said. "They're not allowed to do that. That's not right."

Fred Cate, a privacy expert and law professor at Indiana University's Maurer School of Law, said such behavior erodes public trust in the federal government and that the agents involved violated the law. "Clearly this is rogue activity," Cate said. "No question about it." Cate said agents committed two separate offenses: Getting the information outside of legal channels and then using it to impersonate Salkin. Just because they were operating in an undercover capacity does not make them free to break other laws, he said.