No later than January 1, 2019, each state or local law enforcement agency subject to this chapter shall do all of the following:
1. Formalize in writing any unwritten, informal policies relating to the enforcement of immigration laws.
2. Update the agency’s policies to be consistent with this chapter, to require each officer or other employee of the law enforcement agency to fully comply with this chapter, and to prohibit an officer or other employee of the law enforcement agency from preventing law enforcement agency personnel from fully complying with this chapter.