President Donald Trump’s memo Tuesday seeking to block undocumented immigrants from being counted for congressional seats is invoking the litigation over the administration’s failed attempt to add a citizenship question to the 2020 census.

The executive action claims the president has the authority to exclude undocumented immigrants from the population count used to determine how many House seats each state has. But experts, including litigators who challenged the citizenship question, immediately called foul. Several groups promised to sue once again over the memo, setting the stage for another series of legal fights involving the census.