I go to UND and monitor all the time. As far as I know it is not illegal in the state of North Dakota to monitor. The laws could vary by community. However, in Grand Forks I had my hand-held scanner on and visible in front of the police and secret service during the Obama/Clinton speech in Grand Forks. If they let me listen to it there they will let me listen to it anywhere. It is illegal to use a scanner in MN right across the river however BUT if you have a Radio License from the FCC, which is not too hard to obtain it is legal.
It was also ruled that it is LEGAL for licensed amateur radio operators who have a copy of their FCC license in their possession to operate a radio/scanner capable of receiving police and other emergency service frequencies in their vehicle ANYWHERE in the USA.