Indicted Milwaukee County Circuit Judge Hannah Dugan believes she is shielded from prosecution in a federal case accusing her of obstructing the arrest of an illegal immigrant who was before her court, according to a filing submitted by her lawyers on Thursday.

Dugan was arrested in April and indicted by a federal grand jury earlier this month on obstruction charges for her alleged role in helping the migrant evade immigration authorities in her courthouse. The Milwaukee judge pleaded not guilty in the case set for trial on July 21.