When Can a LEO Ask for a Breathalyzer Test?

Until the subject came up concerning a recent boating accident, we had never considered when or why a law enforcement officer could legally ask for a breathalyzer test. Here's what the law says:

Alabama’s implied consent law specifies that any person who operates a vehicle within the state is deemed to have consented to a blood, breath, or urine test to measure blood alcohol content (BAC). However, a driver is required to test only if lawfully arrested for driving under the influence (DUI). In other words, the officer must have reasonable grounds to believe the person was driving under the influence to request a BAC test. These chemical BAC tests are used to determine if a person is safe to drive or over the legal BAC limit and for evidence in DUI trials.

In other words, unless a person is staggering, slurring his/her speech, acting in a belligerent manner, or reeking of alcohol, a LEO has no authority to request any test to determine the person's BAC. He can request such a test only after he arrests the subject for DUI/BUI. 

So how did law enforcement have the authority to test Trey Wooten? We can think of two reasons, but since they're just guesses, we won't state them here.

Instead, let's say a prayer for Lauren's family and Blakely's family. This is still just the beginning of their hurt. A manslaughter case can drag on for two to three years; during this time the family has no resolution and finds it hard to get on with their lives. They deserve the public's support...not the public's bickering and finger pointing.