Potential candidates must be at least 18 years old, though most police precincts will not accept new recruits under 21. If you apply at 18 and the precinct accepts you, you will work a desk job until you reach the minimum age requirement. You must be a U.S. citizen, maintain a valid driver’s license and submit to a background check. A felony conviction on your record may disqualify you from becoming a police officer. You must also meet demanding physical requirements.