Rocklin police said the teenager was upset her parents wouldn't let her use the Internet after 10 p.m., so she bought them milkshakes Dec. 28 and spiked them with her friend's prescription sleeping pills, KOVR-TV, Sacramento, reported Thursday.
Lt. Lon Milka said the parents thought the milkshakes tasted odd and only consumed about a quarter of them, but it was enough to make them fall asleep for the night.
Milka said the parents took a drug test and confronted their daughter, who admitted drugging the shakes to circumvent their Internet restriction.
The teen and her friend, whose names were not released because they are 16 and 15 years old, were arrested Monday on charges of conspiracy and willfully mingling a pharmaceutical into food.
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