Boustany sued the author and publisher of "Murder in the Bayou" in October, when he was in a tight Senate race competition. Boustany lost the race in November and ended his lawsuit this month. Boustany lawyer Jimmy Faircloth confirmed the lawsuit dismissal Tuesday.
"He felt as though it would probably be best for all concerned for him not to proceed with the lawsuit," Faircloth said.
Author Ethan Brown and a spokesman for publishing house Simon & Schuster said they are pleased with the decision.
Brown's book, about the killings of eight prostitutes in Jefferson David Parish, includes a chapter claiming Boustany was involved with some of the women. The book, which cites multiple anonymous sources, does not allege that Boustany was involved in the slayings.
The book's release last month came at a sensitive time for Boustany, ahead of the Nov. 8 election in which he was among the leading candidates in the race for an open U.S. Senate seat. He came in third. Republican state Treasurer John Kennedy won the runoff last weekend and will be sworn in as senator next month, while Boustany will end his tenure in Congress.
Boustany called the prostitution allegations lies, and his lawsuit claimed Brown's book included the chapter on Boustany to "sensationalize the story" and "to boost sales" with disregard for the truth.
The congressman still believes the information should never have been published and is indefensible, Faircloth said. But he added that "continuing the lawsuit probably would have resulted in a lot more publicity to this."
Brown's book also says a former Boustany employee was involved in the operations of a Jefferson Davis Parish hotel that allegedly was frequented by the prostitutes. The defamation lawsuit didn't challenge those claims. Boustany has said the employee hid the hotel information from him and left the congressman's office in September.