Arrest can be made even for obscene hand gestures such as giving someone the finger
Using inappropriate language is a big No. Even the tone of voice used in communicating with officials can cause serious grief.
If you have an urged to show affections, wait until you get home or to your hotel. Public displays of affection, such as kissing can land you in prison.
If you done illegal drugs even for recreational proposes elsewhere, forget about it in Dubai. Penalties for possession of any sort, use for personal reason, or trafficking in illegal drugs in the United Arab Emirates are extreme. Anyone convicted of offence related to drugs can expect long jail sentences and heavy fines.
You need a permit to possess Alcohol. Remember if you are drinking or have alcohol on you without a Ministry of Interior liquor permit, chances are very high you will be arrested and may spend some quality time in jail or may be paying fines.
Even if you consume alcohol in a hotel or a bar, technically you need your own personal liquor license.
If you are drinking in public and causing a scene or if you are drinking and driving in Dubai, regardless of one’s blood alcohol content level, it is considered serious offenses. If you are arrested on alcohol-related charges, you will be staying in jail for number of days until your hearing in court.
If you are a Muslim who is arrested for any of the drinking related offenses, be prepared for lashings regardless of your citizenship
If you are selling illegal drugs in Dubai the maximum penalty is Death.
Even if you are transiting in Dubai or anywhere else in UAE even trace amounts of illegal drugs can result in you going to jail for four years.
Don’t bring poppy seeds to Dubai even for cooking purpose; it will land you in jail.
Make sure you have enough money to cover the checks you write; passing bad checks in Dubai will not affect your credit rating but it will affect your tolerance of living in confined places, yes it will land you in jail.
Only buy what you can afford if you are not able to pay your bills and yes this includes even the hotel bills, be ready to go to jail or pay fine. If you are just visiting be extra careful; Bail normally is not available to non-residents of the UAE who are arrested for crimes involving fraud.