The Denver Post reports that U.S. Reps. Diana DeGette and Jared Polis praised the move in a letter Thursday.
The university's board of trustees approved the new rate in June. It allows illegal immigrants who graduated from Colorado high schools to pay $3,358 per semester, a rate that's lower than the out-of-state rate, but higher than the in-state rate.
Republican Attorney General John Suthers issued an opinion after the board's decision saying that the tuition discount amounts to a "public benefit" that illegal immigrants are not entitled to under state and federal laws.
The university has stood by its decision.
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