Arrest the parent, not the child.

Police in Des Moines, Iowa, arrested a twelve-year-old girl for trespassing when she refused to leave a senator's office as it was closing, during an anti-war protest. Her mother, who was outside on the sidewalk, was ticketed for contributing to the delinquency of a minor.

First of all, while I don't like the cause for which the child was protesting, the police were fully in the wrong to arrest any peaceful protester. Peaceful protest is protected speech and assembly under the first amendment. The most the police should have done was forcibly remove the girl and the woman who remained in the office to the sidewalk outside.

Second, the kid was twelve years old. The police should have arrested her mother, run both of them in, and called her father to come pick her up.

However you want to look at it, the girl's mother got off too lightly, and the police overreacted.