Karen Read Source Calls Lawyer Alan Jackson Hugging Her 'Innocent Goofing'

A photo of Karen Read 's attorney Alan Jackson embracing her tightly from behind is as innocent as her fans believe she is in her murder case ... at least according to people in Karen's inner circle.

The photo, taken outside a Smith & Wollensky restaurant in Boston, has created a big stir around the high-profile case since it was taken on June 27. The jury was in the middle of deliberating ... deciding whether Karen had indeed murdered her police officer boyfriend John O'Keefe .

But, a source close to Karen tells TMZ ... the image is being taken out of context, as it was actually an innocent moment of celebration -- and there was "nothing to this other than goofing around."

We're told Alan, Karen and friends -- including Alan's co-counsel David Yannetti -- had dined at the restaurant ... and they were feeling good about the case, as the jury had been deliberating for 3 days, at that point.

According to the source ... 10 minutes before the pic was taken, they were all inside the restaurant and Jackson had come up behind Yannetti and given him a similar hug, but also added a kiss on his cheek.

Of course, as it turns out, they had good reason to be celebrating ... a few days later the jury came back deadlocked, and the judge declared a mistrial. Prosecutors have vowed they will retry Karen ... but, for now, she's a free woman.