No matter how righteous their objectives are, it is wrong to disturb other unrelated people. Of course, it is understandable that by participating in protests, protesters are showing their anger, dissatisfaction or even resentment. However, it does not grant them rights to obstruct uninvolved people from living their daily life. Just imagine a situation when you have urgent things to do like driving your sick child to the hospital but the fastest road is being blocked by a mob of protesters. How will you feel ?
Yes, protesters should face criminal prosecution when they block public roadways and interstates. When they block these roads, people are prevented from seeking medical care or from completing the tasks they need to be able to complete. People should be allowed to protest, but the protests should not interfere with the lives of others.
While protestors definitely have the right and need to protest injustice and let their voices be heard, doing so by blocking public roadways and intersections is still a traffic hazard. The road should be saved for vehicles because vehicles cannot go on the sidewalk, but protestors can, so if they choose to be a traffic hazard then they should be warned, given the opportunity to move, and if they do not move, then they should be prosecuted.
Protests abide by the age-old allowance of free speech. However, this should take place under certain guidelines, one of which contains protesters by preventing them from blocking areas that all individuals need to use, such as roadways and highways. Just because one side needs to raise their voice doesn't mean that all should get involved by having to work around what the protesters are saying and doing.
No, protesters should not always be prosecuted, even when they block roadways. They do need to be kept safe, and others around them need to be kept safe, and they should be encouraged to move their protest to a safe place. But there is no need to automatically prosecute protesters especially when there are serious crimes to prosecute.