U visa:

The U visa category is for those who entered in another nonimmigrant visa status but who are prevented from timely departure or fail to maintain status because they suffered substantial physical or mental abuse as a result of having been a victim of criminal activity involving a violation of one or more federal, state or local criminal statutes relating to rape, torture, trafficking, incest, domestic violence and other such similar crimes.

The victim must provide information helpful to the investigation or prosecution of the crime, and a petition for U visa status must be accompanied by a certification from a law enforcement agency involved.

Nearly all grounds of inadmissibility may be waived, and individuals in U visa status may adjust to permanent residence after three years. A maximum stay of 4 years in U status is allowed. U visas are limited to 10,000 per fiscal year.