A Pinellas sheriff's detective says that in an effort to seek out homegrown marijuana, he donned a Progress Energy uniform as a "ruse" and then entered a homeowner's property without a search warrant.

The deputy's comments came in a formal interview with an attorney representing people charged with growing marijuana.

When the Tampa Bay Times showed the interview transcript to Sheriff Bob Gualtieri, he quickly disavowed the tactic.

"I was appalled by it," Gualtieri said Wednesday. "I think it's wrong. It's not what we should have been doing at all." He said he did not know of the incident until contacted this week by the Times.

Gualtieri said that he instituted a new policy Wednesday preventing deputies from using corporate uniforms without permission from their own supervisors and "express written permission of that corporate entity."

While wearing the uniform, Detective Paul Giovannoni found no evidence of marijuana, and the resident of the home was not charged with any crime.

But the revelation follows others about tactics the Sheriff's Office used while investigating "grow houses," and conducting surveillance on the Simply Hydroponics shop in Largo. The Sheriff's Office used a camera outside the store, which has since been removed, to gather information on customers. In one of the investigations, a deputy was suspended for five days for mishandling evidence.

Attorney John Trevena, who conducted the interview of the detective, called a deposition, called it "indicative of problems with the narcotics unit at the Sheriff's Office that go beyond just this trespassing incident. … It is apparent now that this is a rogue unit, and there needs to be an outside agency to investigate."

A law professor who reviewed the deposition at the request of the Times, Bruce Jacob of the Stetson University College of Law, said "that's obviously an illegal tactic to pretend that you work for Progress Energy to get on someone's property."

Generally, law enforcement officers need a search warrant to enter someone's property without their permission.

In the transcript, Giovannoni said, "I did attempt, one time, to make contact with a gentleman, I did have a Progress Energy shirt on, and he led me to the rear of his property — actually he led me to the side of his property, and that was it."

When Trevena asked him why, the detective said, "It was just as a ruse, in an attempt to see if — if he didn't let me back there, to see if I smelled marijuana."

Giovannoni said he didn't think he actually called himself a Progress Energy employee, but said the resident probably assumed he was one.

Giovannoni acknowledged he had not sought a search warrant. Early in the interview he denied using a uniform in this way, but he brought it up himself later, saying he had forgotten it.

The sheriff said he spoke to the detective's supervisors about the incident Wednesday, and provided this account:

Gualtieri said Giovannoni never intended to go to the resident's back or side yard. But Giovannoni did intend to get the resident to open his front door, in hopes of glimpsing or smelling marijuana plants inside.

But Gualtieri said the homeowner began asking about problems he was having with his power usage, and went around the house to the meter. So Giovannoni went along, essentially caught in his own ruse.

But even going to the front door in a phony uniform wasn't proper, Gualtieri said. If he had been in a deputy's uniform, the resident could have decided whether to open the door. This way, he didn't know he was opening his door to law enforcement.

Gualtieri called it "contrary to good policing and respecting individual rights and it's wrong." If the detective had smelled marijuana and used that information to get a search warrant, "I don't think it would pass constitutional muster," said Gualtieri, who also is a lawyer.

That sounds a different note from another sheriff's employee, Cpl. Michael Sciarrino, who gave a sworn interview with Trevena. Asked about the uniform, Sciarrino said, "I don't think that that's improper because Progress Energy would have the right to go up to their own meter during normal business hours to do it, so that's where I was falling under the assumption that he would be able to do that."

Although Gualtieri criticized the tactic, he was less quick to criticize his detective. "He's a young detective who I think thought he was just being creative," Gualtieri said. "I put more responsibility with the supervision." He said he wanted to think about whether to discipline anyone.

Giovannoni said in his deposition that he got the uniform from a Progress Energy employee.

Progress Energy spokeswoman Suzanne Grant called this "an isolated case of an employee acting alone without approval or authority," and contrary to policy. She said Progress Energy "doesn't permit or support anyone, including law enforcement, to pose as employees." She said customers can call the utility's customer service numbers to confirm an employee's identity.

She said the worker who supplied the uniform no longer works for Progress Energy, but declined to say more.

Curtis Krueger can be reached at ckrueger@tampabay.com or (727) 893-8232.