A patron reported seeing a male and female involved in some sort of a dispute in the parking lot near the station entrance. The reporting party believed that the female was in danger and officers responded to check her welfare. On arrival, officers found the male and female involved in sexual activity in the parking lot. Officers determined that the woman had not consented to sex and the male was detained for investigation of possible sexual assault. The on-call detective responded and interviewed both parties. The male was ultimately arrested for rape and was booked at Santa Rita Jail.