Attorney Drew Findling tells TMZ ... his client broke NO LAWS, and cops used a lane change as a thinly veiled excuse to try and take the rapper down.

Findling, who also reps Gucci Mane, Katt Williams and Trippie Redd, tells us, "It's a common theme. We're talking about a young, African-American man driving a shiny, beautiful luxury car and clad in designer clothes and watches and jewelry."

Findling goes on ... "Unfortunately people in his genre become a target for law enforcement who think that lifestyle is connected to some illegal activity ... and that is a sad statement."

Findling says his client was NOT in possession of any firearm. The attorney says the passenger in Offset's car -- his assistant -- was a licensed gun holder who had firearms in the car for security. Findling notes Offset needs protection because of the large amounts of cash he typically carries and the expensive jewelry he wears.

We broke the story ... Offset was arrested Friday outside of Atlanta after cops say he made an illegal lane change. Police say they found 3 handguns in the car, a small amount of weed and a large amount of cash.

He's been charged with possession of a firearm by a felon, possession of a weapon during a crime -- both felonies -- along with possession of weed and an improper lane change.