The title kind of says it. If I plan to left weights in the morning should I eat a high protein meal the night before or the night after?
First, you should have a healthy amount of carbs before your workout so that your body has enough energy for your lifting and doesn't have to ramp up its cortisol. A large glass of juice would do, for instance, as would a bowl of cereal or any regular breakfast. Don't lift weights on an empty stomach. It's no big deal if there are a few hours between the meal and your workout though.
As for the high protein meal, you should have this immediately after your workout. Your muscles start regenerating immediately after they are exhausted so you need to provide sufficient protein as fast as possible. In addition, you should get in some carbs after the workout to make up for the energy loss. A glass of juice, energy drink, etc. is usually the easiest option.
Protein before your workout would work as well, but the digestion might take a bit of energy away from your workout, and there's no sizable benefit. In any case, waiting until the night after is not an option. That said, you should also have a high-protein meal the night after your workout since a lot of muscle growth takes place while you sleep. But this is in addition to the one after your workout, not as a replacement. Also, since muscle growth will continue for a few days, you should have a high-protein meal every night, not just the night after your workout.
So to answer your question: High protein meal every night, and after every workout.
I have to disagree with M. Cypher that it is no big deal if there are a few hours between your meal and your workout. I think it is absolutely essential to be loaded with carbs in order to be at your full stregth and a glass of juice is certainly not enough. I would eat a large portion of paste prior to working out. But you also need to give your body some time to diggest the food. I asked doctors how long that takes and while no one knew exactly, the best guess was something like 2 hours. To put it short, stuff up, wait for 2 hours and then you are ready to workout.
After a workout you also need to eat to replenish your glycogen, and this is the only time of the day when you can legaly go ahead and enjoy something with sugar. I would not suggest protein directly after a workout, as it will be broken down for energy and it is too precious for that. By giving your body the sugar first, you cover your energy deficit and only at least 30 minutes after eat protein so your muscle can repair.