Good question, I haven't thought about this before
Well I'm tied between yes and no, it is possible and for some reason I think Mrs. Lovett didn't do it

I think she did. Lucy does seem to retain some of her memory, and she really doesn't like Mrs.Lovett for some reason. She keeps calling her a witch and the devils wife. That story that Lovett tried to stop her from poisoning herself doesn't sound convincing.

^ that's probably because she knew Livett was selling people pie. I thunk it was implied that Lucy took it as an act of suicide after being raped.

Maybe Mrs. Lovett lied about that. She kept saying "Poor thing" as if to make herself look more caring. Maybe Lucy was so depressed that Mrs. Lovett didn't see anything wrog with atempting to kill her. She already has shown a blatant disregard for human life, so i wouldn't put it past her.

Maybe Mrs. Lovett lied about that. Maybe now that the man she was crushing on was gone, she didn't see any reason to put up with his wife now. She's already shown a blatant disregard for people that don't benefit her in some way, so i wouldn't put it past her.

It's possible since she wanted Sweeney.

possible im not sure but i feel like it :3

good point maybe

It is possible, but I doubt it. She knew Lucy was still alive, yet never killed her in the years she's known Lucy was a beggar. So I do think Lucy poisoned herself, and Lovett knew but made no effort to stop her. So I doubt she had any kind or sympathetic feelings toward Lucy. So I think she was fine seeing, and letting bad things happen to Lucy, but never did anything too overt herself.

I know this is an old thread but with the recent revival I have been thinking about it. Personally I don’t think Lovett hand fed Lucy the poison, but I do believe she persuaded her to do it. I can only imagine Lucy confiding in her after all of the events with the trial, Benjamin being convicted, and then she might have said “ oh, I think there might be hope from the judge” and the two exchanging conversations of encouragement that he might come home. But the moment Lucy returns after that horrible night of the masked party (Lovett probably was even the babysitter) and feels hopeless now with no way to care for the baby Joanna, just imagine Lovett saying “oh you poor thing, there really is no hope now, you haven’t got any money for you or your baby, etc” and practically points her in the direction so that apothecary…
So, although Lucy/beggar woman may not remember exactly what happened that is why she knows Lovett is “the devils wife” and is constantly calling her evil. Beggar woman knows deep down she manipulates and is cruel at heart so she can get what she want. Every time I watch “God That’s Good!” And you see the interaction between those two you can see how much they hate each other because you know some bad stuff went down after Sweeney was deported.