Personally, to me, this just reiterates that she isn't too smart or, at the least, she doesn't think things through.
I mean, if she doesn't realize it'll likely come out that he's full of it during his first conversation with other law students then I doubt she's thinking about how, in the future, they'll notice he's not a lawyer.

She just doesn't think things through or consider, truly, the repercussions of her actions. I've dated someone like that and I'd say that's enough of a red flag. Being with someone like that means you have to take on the job of thinking of the consequences for them...and since you can't watch them 24 hours a day... a lot of that means putting out the fires they've set.