According to the report, obtained by TMZ, officers noted the 'Real Housewives of Potomac' cast member also had slurred speech and bloodshot eyes when they arrived on scene -- and they say she didn't answer when cops asked her twice how much she had to drink.

Officers also noted she had 2 closed bottles of the alcoholic beverage Stella inside her vehicle.

The report adds that while cops thought Karen appeared to be intoxicated ... she declined to undergo a field sobriety test or a breathalyzer.

Fire rescue, which also responded to the scene, tried to get her to sit on a stretcher -- but the report says she refused both the stretcher and any medical care.

According to officers, Karen also made it clear she did not wish to be recorded when officers told her she was on their bodycam footage.

She was ultimately arrested for DUI, and driven to the police station where she was issued citations ... and later released to her husband, Raymond.

As we reported ... cops told us Karen hit the median and a street sign late Tuesday night while driving her 2017 Maserati -- and a security guard in the neighborhood called the police after witnessing the whole thing.

Huger hasn't addressed the charges yet.

BTW, we spoke with Karen's 'RHOP' costar Candiace Dillard Bassett ... who filled us in on the folks showing her tons of support following her crash -- as well as what it might mean for Karen's future on the series.