I've never been on a jury and live in a country that doesn't have juries at all, as far as I'm aware, but if I lived in the US and served on a jury there, I would never convict solely on police testimony. The police are often not a neutral party. And especially with all the stories of police quotas, extremist groups infiltrating the police, rampant racism in some police departments, and even law enforcement experts telling people to never talk to the police without a lawyer, the US police doesn't come across to me as particularly trustworthy.