College student helps investigators arrest San Mateo police officer accused of preying on minor

SAN MATEO, Calif. (KGO) -- On Friday morning, we heard from the college student who helped investigators arrest a San Mateo police officer accused of preying on a minor.

Officer Robert Edward Davies is accused of trying to set up a sexual encounter with a 16-year-old girl on Snapchat. But it was not an underage girl, it was a college student posing as a teen.

The college student named "Ethan" spoke to "Good Morning America."

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"I found out that with the gender filter, I made me a very pretty girl so I decided to take advantage of it and try to make a tinder account to capture pedophiles. He asked me to tell him about myself. So I told him, my name is Ester, as you know, and I'm 16 and I like comic book movies and Star Wars."

A criminal investigation lead to Officer Davies' arrest.

He was charged with contacting a minor to commit a felony.