Long before Sunday's parade bloodshed, the alert was active for more than five years after he allegedly skipped out on bail and moved to Wisconsin.
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The I-Team has learned Brooks was released twice this year by Wisconsin authorities, despite the warrant for his arrest in Nevada.
When dozens of people were run down by Brooks and his red SUV, according to authorities, only then did this sex offender warrant from the southwest become important. It raises a question: when Brooks went before Wisconsin judges twice this year on other charges, should he have been sent back to Nevada?
The warrant calls him "non-compliant," meaning he didn't continue registering as a sex offender for a November 2006 statutory sexual seduction of a Nevada 15-year-old who had become pregnant.
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Former federal prosecutor and ABC7 legal analyst, Gil Soffer, told the I-Team state sex offender warrants are not always clear cut.
"Every state has its own rules," Soffer said. "Nevada has its own rules about when and whether it will extradite on a warrant. So, it just depends. It depends on the state, depends on the crime."
The 2006 sex case in Nevada was followed by another sex charge there in which Brooks allegedly skipped bail and headed to Wisconsin.
Earlier this year, and again earlier this month, he was arrested on separate charges, but not turned over to Nevada authorities.
As the I-Team reported Monday, in the November case he is accused of running over his child's mother with his vehicle, but was freed on $1,000 bond that state prosecutors have already questioned as too low.
"I don't think there's any question the prosecutor is trying to get ahead of this and manage what looks simply terrible, given the gravity of this crime," Soffer said. "All eyes are on what happened previously and that bond certainly looks low given the nature of the prior offense."
Bond for Brooks is now set at a much higher mark: $5 million. Prosecutors always say bond is intended to ensure a person returns to court and doesn't suddenly relocate. They point to Brooks' history in Nevada as someone who should not be trusted with a low bond.