
Rules Question: Arm Bar
If by fending them off you mean pushing them away then no. If you established your arm bar without pushing them (or hitting them in the gut etc) then this would be ok (general rule 45 degrees with no extending of it).
The offender has priority unless the defence LEGALLY gets in their way (or the offence goes out of their normal motion - ie extending their forearm or dropping a shoulder to deliberately make contact).
If the offender uses the arm bar to protect the ball without going out of their normal motion, and without making (significant) contact with a legal defender then that's ok
Hope that makes sense :)

Basically he/she's allowed to hold the arm bar there to protect the dribble, as long as it's not pushing the defence away or 'fending off'. 45 degrees is a general rule - high enough to protect the dribble and still low enough that it can't be used to hold the defence away. It must be HELD - as soon as the forearm is extended at all it is a foul.
In regards to the defence, it depends what situation you mean. No hands are technically allowed on the dribbler but unless the offence is disadvantaged then it probably won't be called. Just make sure you listen to the ref, he/she will most likely yell at you to get your hands out before they call a foul. 2 hands on should be considered an automatic foul.
For a post player 1 arm bar is allowed in the back but as soon as the offence turns and faces this must be removed. Again the 45 degrees is a general rule here, and again 2 arms is an automatic foul. Just listen to the ref though, most times they will tell you a few times before they call it
