Trump aims to bar undocumented immigrants from counting toward House representation

The order, which will almost certainly face legal challenges, amounts to something of a workaround for Trump after the Supreme Court last year blocked the administration from adding a citizenship question to the decennial survey.

The rationale for the memo rests on the argument that the president has final say over transmitting the final census report to Congress and that the constitution does not explicitly define which persons must be included in determining apportionment.

"The discretion delegated to the executive branch to determine who qualifies as an 'inhabitant' includes authority to exclude from the apportionment base aliens who are not in a lawful immigration status," the order states. "Excluding these illegal aliens from the apportionment base is more consonant with the principles of representative democracy underpinning our system of Government.

The order implicitly calls out California — a state represented overwhelmingly by Democrats in Congress — in making the argument for discounting undocumented immigrants, noting that "one State is home to more than 2.2 million illegal aliens."

"Including these illegal aliens in the population of the State for the purpose of apportionment could result in the allocation of two or three more congressional seats than would otherwise be allocated," the order states.