Why would a park be any different than any other area where people are present.
Many of the parks that I have visited have walking and biking trails where a person could hide and jump a victim. Making a park a gun free zone might encourage such activity.
Central Park Jogger caseThe Central Park Jogger case involved an assault and rape that took place in New York City's Central Park on April 19, 1989. The victim was Trisha Meili. Five juvenile males were tried and convicted for the crime. The convictions were vacated in 2002 when another man claimed to have committed the crime alone and DNA evidence confirmed his involvement in the rape.
VictimTrisha Meili (born June 24, 1960) was the victim often described in the media as the Central Park Jogger. Raised in New Jersey and Pittsburgh, Meili received a Bachelor of Arts from Wellesley College, a Master of Arts from Yale University, and a Master of Business Administration from Yale School of Management. She worked at the Wall Street investment bank Salomon Brothers. Meili was referred to simply as the "Central Park Jogger" in most media accounts of the incident. However, local television stations did release her name in the days immediately following the attack, and two newspapers aimed at the African-American community, The City Sun and the Amsterdam News, and radio station WLIB continued to do so as the case progressed.<1> In 2003, Meili confirmed her identity to the media, published a memoir entitled I Am the Central Park Jogger, and began a career as an inspirational speaker.<2><3>
AssaultOn April 19, 1989, the slightly-built 28-year-old investment banker was violently assaulted while jogging in New York City's Central Park. She was raped and beaten almost to death. When found about four hours later, she was suffering from severe hypothermia and blood loss from multiple lacerations and internal bleeding, and her skull had been fractured so badly that her left eye was removed from the socket. The initial medical prognosis was that she would die or, at best, remain in a permanent coma due to her injuries. Remarkably, she largely recovered, with some lingering disabilities related to balance and loss of vision. As a result of the severe trauma, she had no memory of the attack or of any events up to an hour preceding the assault.
http://en.wikipedia.org/wiki/Central_Park_Jogger_case