Final answer:
The police were called to Ana Hidalgo's anti-homecoming dance for various reasons, including protests turning violent, interrogations, illegal activities, physical altercations, arrests related to clothing choices, and enforcement of laws against same-sex dancing.
Step-by-step explanation:
The police were called to Ana Hidalgo's anti-homecoming dance due to various reasons. In the first reference, police were called to a protest march and meeting in Los Angeles in 1970, which turned violent and resulted in the death of three activists. In the second reference, police were called after an officer interrogated two women who were involved in a separate incident. In the third reference, police circled a room where individuals were dancing and engaged in activities that were considered illegal at the time. In the fourth reference, police were called after an officer attempted to handcuff a woman, leading to a physical altercation. In the fifth reference, police were called during the Zoot Suit riots in Los Angeles, where Mexican American youths were arrested based on their choice of clothing. In the sixth reference, police were called to a bar where individuals were dancing in same-sex couples, which was considered against the law at the time. In the seventh reference, police circled a bar and individuals quickly switched partners to comply with the law.