Q. I’m a Frum woman that has a Jewish girlfriend, and she has a Jewish male tenant who lives in her house. Would it be Yichud for me to sleep over in her home on Shabbos? She is divorced so there is no husband in the picture and she’s also an empty nester so no kids around either. I know it’s yichud for her but she doesn’t really care. Is it permitted for me to stay in that home overnight during Shabbos?

A. In principle there is a Yichud (unethical seclusion prohibition) between one man and two women.
On question 1688 regarding a shidduch date and the prospective Chosson came to the apartment, the mother of the young lady was present, as were her two daughters. However, her husband was at work. We wrote: “See Shulchan Aruch (E.H. 22: 15) and in the Poskim therein as to how many women are required to avoid a yichud prohibition.

Horav Shlomo Miller’s Shlit’a opinion is that if there are two present besides the proposed Kalah there is no yichud. Otherwise, the home door should be left unlocked or the meeting should take place in a room with an uncovered window facing the street. If the husband is out of town, a neighbor should be asked to check on the home. An inside security camera could also be set.
He also strongly suggested installing video-surveillance (a recording machine) as advised on question 346.

In your particular case you may add that surveillance on your own phone, after asking permission from your host.

See also question 974 regarding a two bedroom apartment, if a man and women can share the bathroom and kitchen while each lives in a separate private room with locks on door? What if there are more tenants? Would a security camera make a difference?

Horav Shlomo Miller’s Shlit”a opinion is that sharing an apartment in the particular setting you describe is not a good idea as it can easily lead to the yichud prohibition of seclusion and then promiscuity, even if more people reside in the co-ed flat.

In question 346, Horav Miller recommended adding a security camera for office employees or for an elderly patient left alone with the female care-giver in question # 828 to avoid yichud.

We there mentioned that Horav Nissim Karelitz Shlit’a (quoted in Moriah-Elul 5771 p.146) maintains that security cameras are to be regarded as an open door to the street in regards to the yichud prohibition, which the Noda Beyihuda (E.H. 71) permits. He mentions that they do not have to be scrutinized on real time, as long as there is a possibility that the tape (or digital recording) could later be seen, and it is therefore an effective deterrent.

Rabbi A. Bartfeld as revised by, Horav Dovid Pam, Horav Aharon Miller, Horav Chanoch Ehrentreu and Horav Kalman Ochs Shlit’a