Can flipping a cop off be probable cause for a public intoxication arrest?

Flipping off a cop alone is not probably cause for arrest. However, that together with the officers observations (smell of alcohol, unsteadiness, slurring of speech) can be probable cause for an arrest. Hire an attorney to handle this for you. Sobriety tests are not a requirement for a conviction although the lack of any tests can be used in your defense.

That's not the smartest thing I ever saw. None of my clients ever benefited from being rude to the police that being said it is not by itself probable cause for arrest for drunk in public. However, it gives the police reason to investigate and they probably have additional reasons for the arrest. Hire an attorney to represent you.

Police irritation never ends well for the layman. Once you annoyed him, he naturally became interested in checking to see if he could accuse of something. Drunk in public does not require field sobriety tests in order to get a conviction, but it can be harder for the officer to prove if he did not do anything to determine whether you were really drunk or just being rude.

When an officer charges one of my clients with public intoxication it is based on a "totality of the circumstances". That means he/she can approach you after he/she witnesses you flipping them off (which others on here have pointed out was not the best decision) and get an assessment as to whether or not you appear to be intoxicated.

It depends. By itself, probably not. But since they can't arrest you for "contempt of cop" they will look to see if you were in a public place, and whether you consumed enough alcohol to affect your manner, speech and/or disposition.