Riley was a star baseball player at Serra High School in San Mateo, and later at San Joaquin Delta College in Stockton.
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Friends say Riley and a friend noticed someone suspicious watching them that night, but were focused on their phones.
Friends and family initially thought it was a random attack, though Riley says his own research suggests otherwise.
U.S. Park Police released sketches of a possible gunman based on surveillance video a few weeks later, but no solid leads materialized. No motive or suspect was ever identified.
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Riley was on ABC7 News Getting Answers, and told anchor Kristen Sze that he has returned to the Bay Area on this five year anniversary to renew attention on the unsolved case.
Riley has organized a service and candlelight vigil at St. Gregory's Church in San Mateo on August 6th at 7pm, all are invited. Riley, now divorced, says losing Calvin has destroyed his family. Now living in Boston, Riley says U.S. Police have not pursued the case with urgency. He wants to remind the public there is still a $110,000 reward and a Facebook page called Justice for Calvin Riley.