Consequences of having a fake ID?

what are the consequences of each of the following situations:

1. You are walking down the street. A policeman stops you, searches you and finds a fake ID. You were not using it at all, you just have it with you.

2. You are getting into a concert. The security guard realizes the ID is fake. What does he do?

3. You successfully got into a concert with the fake ID. In the middle of the concert, police comes in and says they have to check IDs (apparently this happens sometimes) to make sure nobody's under sixteen. They find your ID, and realize that it is fake. You haven't gotten drunk, (or bought a drink, for that matter), and you did not get into trouble or something.

What would happen in each one of these situations?
I'm not actually considering getting a fake ID. I'm just really curious about what would happen... Is it actually against the law, even if you don't do anything like get drunk and beating someone up?

and if i'm a minor...??
here in switzerland, 16 is old enough to get into concerts, buy beer and wine etc, so i'm more curious about the situation here, actually. i mean, they wouldn't arrest a minor, would they?

1. You'll probably be arrested.
2. The guard will often just let you in. The law in most places doesn't assume that people will recognise fake IDs, so it's not illegal for them to let you in if you have one. Of course it's still illegal on your part, but security guards aren't cops so they don't care. Your money's as good as anyone else's. Of course it's also likely the guard will tell you to piss off.
3. You'll probably be arrested.

You can be arrested as a minor. In Switzerland the age of criminal responsibility is ten. There are different provisions in Switzerland's criminal law for those aged 10-15 and those aged 15-18. As I understand it, punitive sanctions like fines and imprisonment cannot be applied to those aged under 15, and the maximum sentence for someone aged 15-18 is one year imprisonment. Although you'd certainly never get that just for having a fake ID.

It is of course it is against the law to simply possess a fake. In all cases the police will either take you to jail or issue you a ticket. Either way you will end up in court.

The security guard will probably call the police. That way if later the establishment has someone else slip through the cracks they can show that they take action and cooperate with the police. This protects them from liability and protects their licenses.

In most states and most places, you get charged with posession of a fake id, lose any driving priveleges for a while and get a fine.