We moved to a new house two weeks ago tomorrow so our pet cat has been kept in and has been using a litter tray. Our old house had a catflap so the cat didn't use a litter tray. DH says that once we are able to let the cat go outside we can get rid of the litter tray. I think we need to keep it as we won't necessarily be able to let her out when she needs to 'go', either because we're not in or because it's night time. Who is correct?
Of course she needs one if you don't have a cat flap. If your DH tries to say otherwise, tell him he can only use the toilet between 8am and 9pm and if he needs to go overnight he can just hold it all in - as that's what he's asking the cat to do.
I would keep one - if the cat becomes used to going outside they should only use it if they get caught short.
It prevents any accidents, and also the cat having to hold it in.
As an aside we have two cats who "hold it in" occasionally (no catflap and one refuses to use litter trays while the other doesn't like the other cats using "her" litter tray) - both have had cystitis where none of ours other have ever had it. I can't say if it's related but the vet did say it's a possible cause.