Washington state mall shooting suspect Arcan Cetin could face another investigation related to his voting record and his status as a non-citizen.

Katherine Engelbrecht of the voter watchdog organization True The Vote wrote in a letter to Washington State U.S. Attorney Annette Hayes Sunday that the most recent data from the Washington secretary of state shows that Cetin registered to vote on Sept. 27, 2014, despite his illegal legal permanent resident status.

He later voted “in the 2014 General, 2015 General and 2016 Primary,” the letter said.

“His voter registration at the time of this letter’s submission is still listed as Active, according to public records,” Engelbrecht writes.

Engelbrecht notes that federal law 18 U.S.C. § 611 prohibits “any alien” from participating in federal elections while the National Voter Registration Act of 1993 mandates that individuals wishing to register to confirm their U.S. citizenship.

The Washington state voter registration form also explicitly states that those who cannot attest to the same shall “not complete this form.”

The punishment for voting as a non U.S. citizen could result in a sentence of five years in prison or a $10,000, according to the Secretary of State’s Office.

“We don’t have a provision in state law that allows us either county elections officials or the Secretary of State’s office to verify someone’s citizenship,” Washington Secretary of State Kim Wyman told KING 5. “So, we’re in this place where we want to make sure we’re maintaining people’s confidence in the elections and the integrity of the process, but also that we’re giving this individual, like we would any voter, his due process. We’re moving forward, and that investigation is really coming out of the investigation from the shootings.”

“The penalties are very serious. That’s why we want to make sure we’re very measured, and this is why we want to make sure we’re very calm and purposeful in how we move forward,” Wyman said. “The stakes are very high on both sides. You want to keep the confidence level high, but you also want to protect the voting rights of everyone.”

Cetin’s voting record surfaced as certain members of Congress want answers from United States Citizenship and Immigration Services as to why so many individuals are being granted U.S. citizenship at an high rate and hundreds have already mistakenly been naturalized.

Cetin is accused of killing five people during a shooting rampage at the Cascade Mall last Friday. He came to the U.S. at 12 years of age from Adana, Turkey, and graduated from high school in last year in Oak Harbor, a rural area about 30 miles from the mall.

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