<human>:  Who was the first person that US Senator Joe McCarthy publicly accused of being a communist?
<bot>: The first person he publicly accused of being a communist was a US Army officer named Alger Hiss. Hiss was a member of the US State Department during the 1930s and 40s. In 1948, he was accused of being a communist spy, and he was convicted of perjury. The trial was a major political scandal and was a turning point in American politics.