IN response to a recent investigative report on sex tourism in Costa Rica, child advocacy group Casa Alianza is collecting evidence and building cases against local pimps, director Bruce Harris announced Wednesday.Reporters from ABC News Detroit, in Michigan, and the daily La Nación recently revealed that nearly 200 men traveled from Michigan to Costa Rica recently for fishing and sex.The exposé came out in La Nación on Sunday but has yet to be aired in the United States.When it is, Casa Alianza says it will use the tape – along with recordings of three other recently filmed TV programs from news outlets in Spain, Great Britain and Canada – in cases it is building against individuals and organizations that benefit financially from selling sex. Although prostitution is legal in Costa Rica, pimping is not.“It has gone too long where the interest has been focused on the victims, and not even necessarily in a humanistic way. I want to focus now on the pimps,” Harris said. The group of tourists who are the focus of the ABC Detroit report has traveled to Guanacaste for years to participate in an annual fishing tournament, called the Michigan Boys.Women reportedly paid an organization $200-300 for the right to enter the Flamingo Marina Resort, where some the tourists were staying, La Nación reported. Harris said they are investigating an individual they think is behind the organization.The women stayed at nearby hotels and were allowed to enter the hotel only if they were on a list, which included approximately 73 names, according to La Nación.The journalists did not, however, report witnessing any cases of underage prostitution.