Do I need a US Visa for a 14 Stop Over in Miami Flying to Jamaica?
 

Hi forum,
I'm flying to jamaica and have a 14hr stop over in Miami... will I need a visa and will it be a problem having a criminal record to visit the USA between flights?

You will need to go through US Immigration and Customs at Miami, regardless if you're only in the US for a few hours or a few months. If you're not eligible to enter the US, you will be refused entry and sent back to wherever you flew in from. If you do need a visa and don't have one, the airline at your departure airport won't even let you on the plane.

I second everything that @catocony has written. I'll add that if you are from a country whose citizens are eligible for the Visa Waiver Program, you should apply for ESTA online to see if you are approved or need to apply for a visa.

The US has no outgoing immigration check, you can walk freely between international departure gates and the street--I have actually done so twice when our flight was delayed 8 hours. Since there is no barrier there there is no way to do airside transit and thus you must meet the same requirements to transit as to actually enter.

Thus, visa or ESTA if you are a citizen of an eligible country.