to avoid legal troubles

A fresh pair of whittled clogs. ;)

Only slightly tongue in cheek...

Situational awareness combined with retaining a little bit of grey matter between ears.

Assuming it's your first time in the Dam , then you need
1/ A print out of Georges map http://www.amsterdam-red-light-district-maps.com/
2/ Notepad and pen for locations and names ( but be discreet , don't write in public)
3/ Passport , in the 30 years of traveling . i have only had to show my passport once ( in Dan Hagg) but it saved me a whole lot of trouble.

Send Lawyers, guns and money
The shit has hit the fan!

That's what Warren Zevon wished for.

I carry a photocopy of my passport (one in every bag, actually)
and only carry the real passport if I am driving.
Otherwise I leave it in a safe in the room.
That has been good enough for every situation except one, and in that case, where the Phillipines police wanted to see the real thing, they were happy to swing by my hotel to get it. (I didn't do anything wrong, I was in a cab that had an accident with injuries. I know what you were thinking....)

If you try to rent anything...bike, car, boat...they will want to see the real passport.
Most hotels want to see the real passport, as will check-in at airports, and most international rail travel.

Otherwise, you can go almost anywhere with a big smile, and a bigger roll of cash.
Honestly, most people just don't give a shit.
I hate to carry the thing if I am just out for the evening, because I don't want the hassle of getting my pocket picked, and losing the damn thing. I had to replace mine in Frankfurt many years ago. Not fun. Took two days with a photocopy of the thing, AND military ID. Ordinarily, it is 7-10 days.
On the good side, I had a passport for a decade that had "US Consulate Frankfurt, Germany" stamped on the front page, and this confused and frightened the dorks at the airport, making them think I was a diplomat. Sure wish I had that passport back.

Weasel

don't forget - a grinder and skins at all times!

I carry a photocopy of my passport, with the real thing (in the room safe if available) in the room...

unless I'm taking a side trip out of town. Then I take the real thing.

Legally you are obliged to have official valid ID on you at all times. However I carry a cut out page from my old expired passport. The only time I was ever asked for ID was when I reported a robbery. I completely forgot about the ID rule but the police accepted my non valid ID and said it was a good idea.