
“Obstructing justice” is used as a catch-all excuse that law enforcement uses to arrest people doing things they don’t like, whether they’re legal or not. If “obstructing justice” means following ICE around in a car or alerting people to the presence of the police, I’ll actively assist them. On the flip side, if “obstructing justice” means that they’re harboring a murder suspect, I’ll give an anonymous tip to the local police, since they’re the authority that is actually supposed to handle this.
Regardless of circumstance, there is no situation where ICE is the proper authority to call about someone “obstructing justice”. They are immigration enforcement, no more, and they are not anymore empowered to handle such a situation than a federal health inspector is empowered to handle immigration.