The Bonding - S3-E5
Other mistake: It is said that Jeremy Aster's father died five years prior to the events of this episode. However, Jeremy watches a family video recorded by his father in which Jeremy looks exactly the same as he does in the present: a twelve-year-old, when he should be no older than seven.
Commander William T. Riker: In your position it's important to ask yourself one question: what would Picard do?
Wesley Crusher: He'd listen to everyone's opinion and then make his own decision.
Trivia: Another joke from the set designers: whenever someone is in the Jeffries Tubes, you will see several pipes on the walls labeled "GNDN" this stands for "Goes Nowhere, Does Nothing."
Question: Were people able to "lock" the Holodeck doors so that others couldn't just walk in on them? I don't recall an episode where the doors were locked that wasn't because of some malfunction. It seems like Lieutenant Barclay, for example, would either lock the doors during his "fantasies" or have some "fail-safe" that shuts the program off when being walked in on. Otherwise, it's just a really dumb thing to do (for him or anyone playing out a fantasy) knowing they could easily be caught.
Answer: Yes. The doors to the holodecks can be locked when in use by anyone aboard the Enterprise so they couldn't be disturbed. However, high ranking officers like Captain Picard could override the doors as it's seen that overrides are in use even for the crews quarters. Even Barclay, when he's indulging in one of his fantasies could have the doors to the holodeck unlocked by an override code.