Puerto Rico has representation in the US house, albeit non-voting. Only having the right to speak and debate on the floor and votes in committee.
But why does Puerto Rico not have coinciding representation in the senate? And the same for other US territories too?
The House and the senate can set their own rules. There is nothing in the Constitution about non-voting representatives in the House or the Senate.
The Puerto Rican delegates are there at the invite of the House. The House is intended to represent the people/citizens of states of the USA. It is a small step to also wanting to represent citizens of the USA that are not citizens of any state. It is, therefore, perhaps, unsurprising that the House would invite observers from major territories like Puerto Rico. The people in Puerto Rico are citizens, but have no vote in the House as only citizens of the states are democratically represented.
Moreover, there is a tradition of the territories sending delegates to Congress, going right back to 1787. But the delegates, representing the people of the territory, (not the territory) are delegates to the elected chamber: The House of Representatives.
The Senate, which was set up to represent the states sees no need to to have invited observers. Puerto Rico isn't a state so it doesn't have representation in the Senate.
Ultimately I believe this question is based on a faulty premise. Puerto Rico does not have real representation in the House of Representatives either.
The non voting representative is a fig leaf at best, covering the lack of democratic representation.
Puerto Rico has a larger population than 20 US States and would under a representative system receive 4 house delegates. This is a significant vote dilution, which is a violation of voter rights.
The Voting Rights Act, prohibits vote dilution.
Section 2 of the VRA, codified at 42 U.S.C. § 1973, prohibits drawing election districts in ways that improperly dilute minorities’ voting power. This prohibition applies to states, counties, cities, school districts, and any other governmental unit that holds elections.
A recent Supreme court case covered vote dilution in its submission.
“It must be remembered that ‘the right of suffrage can be denied by a debasement or dilution of the weight of a citizen’s vote just as effectively as by wholly prohibiting the free exercise of the franchise.’”
