Violators of the permit rules can face fines and can be ordered to correct the work.
Several electrical and security systems experts interviewed by The Times said there was no practical reason for removing or replacing walls to install a security system. They said the thin wiring can be snaked behind existing walls or run in molding.
Jeff Zwirn, a forensic alarm specialist who runs a firm in Tenafly, N.J., that installs alarm systems, said a security company would almost never tear down walls to run the wiring.
"Even if the person is a movie star, we don't take down walls," Zwirn said. "The average customer would never pay to take the walls down to secure the wiring."
Alarm systems, he said, do not use much power and would not require adding a sub-panel, which feeds off the main electrical panel at the house. That electrical work at Ridley-Thomas' home probably significantly increased the cost of the project and might have been needed to run the air-and-heat unit and the refrigerator, Zwirn said.
Jessica Levinson, a professor at Loyola Law School who studies governmental ethics, said that if the work at Ridley-Thomas' residence was ultimately deemed inappropriate, the supervisor would be responsible, no matter who first suggested the improvements.
"He's not unfamiliar with what it means to be a public official or the state ethics code," Levinson said. "He's the person who said yes to the work. Whether or not the idea started with him, he OK'd the project."
Times staff writer Ben Poston contributed to this report.