The Alabama Law Enforcement Agency says it somehow mixed up the drivers of the two vehicles in its first report of the fatal car accident on April 9 in Mobile County, AL.

Initially, the ALEA claimed Jefferson was driving a 2019 Chevrolet Impala ... before Charles Dunn slammed head-on into it in his 2014 Dodge Charger.

Now, however, the ALEA says Jefferson was actually driving the Charger -- while Dunn was in the Impala.

That means, according to the crash report, cops suspect Jefferson was the one who was under the influence of both alcohol and drugs at the time of the accident -- not Dunn.

It also means, per a diagram of the crash in the report, that Jefferson (labeled Unit 1) is the one who was traveling in a southbound lane before moving into Dunn's northbound lane, headed in the wrong direction, before colliding with the 55-year-old (labeled Unit 2) head-on.

As we reported, Dunn died as a result of the crash. Jefferson -- a former star wideout at Louisiana who was in line to get drafted last month before the wreck -- sustained significant injuries that required several surgeries.

Police told us an investigation into the crash remains ongoing. According to the report, the 23-year-old's blood was taken following the crash, but the results have not yet come back.

Meanwhile, Jefferson's attorney, Brad Sohn, told us on Wednesday he had "absolutely no reason to believe that Michael Jefferson is under criminal investigation or has ever been under investigation."

Dunn's family told us in a statement they now want a public apology from Jefferson and his representatives ... adding, "Charles Dunn never drank or smoked in his life and we would like for his name to be cleared."