Police Officer
Patrol Officer
noun
Those who patrol and inspect are police officers or patrol officers.
巡査 specifically refers to the lowest-ranking officers in the police force in Japan, whose duty is patrolling or doing things around 交番 (police boxes), or responding to emergency calls.
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
その巡査は、スコッチを一気にゴクリと半分飲み干した。
The policeman drank half the scotch in one gulp.