From NBC News:

Data obtained by NBC News from 24 municipal police departments in St. Louis County reveal a gulf between police officer pay in poor, majority African-American northern cities and wealthier, whiter cities further south. Average annual patrol officer pay ranges from $23,000 in Hillsdale to nearly $70,000 in Town and County and Des Peres.

The police pay gap in St. Louis County is mirrored in metropolitan areas and rural communities around the United States, with some officers earning a comfortable middle-class living and others scraping by on poverty and near poverty wages, forced to take second and third jobs to cover basic costs.