Grand and Trial Juries must enforce the Bill of Rights. Grand Juries are part of the executive branch of government, in that they work to enforce the law. Other than that, they are part of the people, and the most important way for the people to enforce the Bill of Rights. One of the worst corruptions of our legal system today is the fact that most Grand Juries have come under the complete control of the U.S. Attorney. Younger makes it quite plain that Grand Juries were effective Bill of Rights enforcement tools before they were co-opted by the lawyers.
Jury nullification is another excellent Bill of Rights enforcement method.
Most of the laws passed by Congress and our state legislatures these days are both unConstitutional and unBillofRightable. Most of these laws are simply totalitarian. They need to be nullified, regularly. Of course, the legal system will protest, most likely violently, and definitely some nullifying jurors will be punished. But that will be temporary.