The 10-year congressman opened two Las Vegas animal hospitals before entering the Senate in 2001.
He says he spent the six months after his resignation getting up to speed on current veterinary practices and volunteering with Heaven Can Wait Animal Society, a Las Vegas nonprofit that offers a low-cost spay and neuter clinic.
"I studied literally every single day for hours and hours, kind of like when I was back in vet school," he said.
For the past year and a half, he has been working full-time at another veterinary practice. Patients often ask the former politician to pose for pictures with their animals.
The two-term Republican senator resigned from office in May 2011 as the Senate Ethics Committee was finalizing a report that said there was evidence he had broken laws. The investigation stemmed from Ensign's eight-month extramarital affair with his campaign treasurer Cynthia Hampton, and from his effort to set up her husband Doug, who also was Ensign's top aide and a close friend, as a lobbyist.
In 2010, after a yearlong investigation, the Justice Department notified Ensign's attorneys it would not pursue criminal charges against him. Questions about why the senator was not prosecuted escalated when federal prosecutors brought charges against Doug Hampton on alleged violations of lobbying law.
Last month, a U.S. district judge gave the Department of Justice 60 days to describe documents it is withholding in the Ensign case and explain why they shouldn't be made public. The ruling came in a lawsuit brought by the watchdog group Citizens for Responsibility and Ethics in Washington. Ensign declined to discuss the scandal in his interview with The Associated Press.
Ensign said he wanted to set up his nine-person practice so that he can do things his own way. He said he sold his last practice in 2002 after he found out that congressional ethics rules barred him from keeping it.
"They made me sell it, and I lost a lot of money, but you had to comply with the rules. It was an unpleasant surprise to me," he said.
He told the Las Vegas Review-Journal this week the he didn't want to hire more than 50 employees, a reference to a federal health care overhaul insurance mandate that exempts small employers.
The hospital will be in keeping with the Sin City aesthetic, with luxury suites for pets and treadmills for hefty canines.
"We want to combine the practice with a pet resort, where your dog or cat can be pampered like they're in a four or five star resort," Ensign said.
The hospital will feature flat screen televisions set to a channel geared at dogs. Owners will be able to pull up a live stream of their animals on their cellphones.
Ensign said he has been surprised at the amount of regulation involved in setting up the hospital, including regular inspections and increased standards of access for disabled people.
"There's so much more regulation today than there has been in the past. Every time you turn around there's something new. It's really remarkable the amount of things you need to comply with now that didn't used to be there," he said.
Hannah Dreier can be reached at http://twitter.com/hannahdreier .
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