U.S. Immigration and Customs Enforcement violated Jeanette Vizguerra’s First Amendment rights by detaining — and planning to deport — the Colorado immigration advocate, her attorneys argued in federal court in Denver on Friday.

A federal judge on Friday heard that the lawyers for prominent Denver immigration advocate Jeanette Vizguerra anticipate amending their petition for her release by adding a claim that officials detained her in retaliation for her First Amendment-protected activity.

ICE says Vizguerra entered the U.S. from Mexico illegally in 1997 and is being held pending deportation. In a statement shortly after her arrest, ICE said the mother of four has a final deportation order and “has received legal due process in U.S. immigration court.”