A video recently released by US Immigration and Customs Enforcement shows agents walking up to the house of a man they were aiming to arrest for deportation. When the door opened, an agent identified himself as a police officer conducting an investigation.

It is reportedly relatively common for immigration agents to pose as local law enforcement officers in order to gain access to or information about an undocumented person they are seeking to detain. The deceptive tactic has faced criticism from immigrant rights advocates and attorneys who say the approach is unethical.

The strategy is also problematic for actual local law enforcement agencies—particularly those in jurisdictions with high concentrations of undocumented residents—that want immigrants to feel safe reporting crimes and interacting with police.

Los Angeles Police Chief Charlie Beck has said the LAPD (which is approximately 47% Latino) will not help the Trump administration deport undocumented immigrants. Beck wants immigrants to feel safe coming forward as witnesses to crime, but even more importantly, the LAPD wants the estimated 500,000 undocumented immigrants living in LA to feel safe contacting the police when they are victims of crime.

While it’s not illegal for federal immigration officers to pose as police, those agents standing outside someone’s house usually do not have search or arrest warrants with them. When there’s no warrant, agents have to receive consent from an adult to come into a home. And that consent is questionable when agents are deceiving the person allowing entry into a home.

In one case, a Texas judge ruled that ICE agents so thoroughly misled the mother of a man targeted for deportation that her consent to enter her home was meaningless and violated the Constitutional protections against warrantless searches and seizures.

The ACLU plans to formally ask Chief Beck, LA Mayor Eric Garcetti, and the LA City Council to ensure that ICE agents are not impersonating LAPD officers.

The LA Times’ Joel Rubin has more on the issue.