By FOX News Radio's Jon Decker at the White House

Imagine you could go on a mini-holiday every weekend and get paid for it. Sounds nice, right? Well, Vice President Joe Biden has found such a deal. For the last five years the Vice President, who pulls in a comfortable $225,496 annual salary (plus a yearly Senate pension of $32,961), has managed to find some extra spending money from a very odd place -- the budget of the U.S. Secret Service. How much extra income? Since 2010, according to income tax returns, Mr. Biden has raked in $113,300 in rental income from the agency that is charged with protecting his life.

So how does this actually work? Every weekend when the Vice President travels home to Wilmington, Delaware, he charges the Secret Service rent to stay in the guest cottage on his property. Yes, the folks that are charged with taking a bullet for the Veep get charged for the privilege of doing so.

Why since 2010 and not earlier in his Vice Presidential term? In early 2010, the long-time tenant of the cottage, the Vice President's mother passed away. Her passing created a vacancy in the cottage. And it also created a nice Christmas fund for the Vice President. Up until 2010, when the Vice President traveled home to Wilmington, the Secret Service rented properties in the Wilmington area for agents who were providing a protective presence at the Vice President's personal residence.

Is the Vice President spending more time in Wilmington? Yes. Since 2010, Mr. Biden has seen the value in going home as often as possible. In 2010, the Bidens took in $13,200 in rental income from the Secret Service. In 2011, more travel back home meant more money in Joe Biden's wallet as he took in $20,900 in rental income from the Secret Service. In 2012, an election-year, the Vice President signed a lease with the Secret Service in which the Agency agreed to pay $2,200 per month. The deal meant that the Vice President grossed $26,400 in rental income in 2012, 2013 and 2014.

Is this illegal? No. "On the surface it sounds outrageous that Biden would be getting money as part of his protection," says Ronald Kessler, best-selling author of First Family Detail. "But it would be unfair to Biden to say you can't rent this property out because you're under protection from the Secret Service." However, Mr. Kessler concedes the Secret Service would likely prevent Biden from renting out the property for safety reasons. Leslie Paige with Citizens Against Government Waste is more troubled by this unique arrangement. "I think it's quite clear that he's lining his pockets." So, although the Vice President's contract with the Secret Service may look bad, there's nothing illegal in Joe Biden charging the Secret Service more than $113,000 for the privilege of guarding Joe Biden.

Isn't Vice President Biden just doing what others in his position have done? No. President Obama derives no additional income when he travels home to Chicago. His tax returns show no rental income attributable to the Secret Service. Former President George W. Bush traveled often during his eight years in office to his ranch in Crawford, Texas. During that time Secret Service personnel stayed gratis in guest quarters on the Bush compound. Similarly, Presidents Ronald Reagan and George H.W. Bush never charged the Secret Service for staying on their properties in Santa Barbara and Kennebunkport. In fact, a Secret Service spokesperson confirms that Vice President Biden is the first occupant of his office to charge the Agency for protecting him.

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