Cornell University Law School says that the Sixth Amendment of the Constitution deals with rights of criminal defendants. This includes the right to a speedy public trial, the right to counsel, the right to know who accused the person of a crime, the nature of the exact crime and the right to a fair jury. This amendment has been tested in regards to terrorism trials in the recent past.
The Sixth Amendment Center explains that anyone who faces potential jail time needs the right to have a lawyer, which is usually seen as the most significant aspect of this amendment. The timing of the counsel is almost as important as having the right to counsel, because many legal decisions are made prior to a court trial.
Intellectual Takeout mentions recent examples where the Sixth Amendment was put to the test. With the National Defense Authorization Act, which was passed in 2011, terrorists who specifically plot against Americans, specifically al-Qaida members, are detained to protect the safety of the public. This exempts al-Qaida members from having a speedy trial with counsel.
Another example given by Intellectual Takeout that muddles the Sixth Amendment is when it interferes with other amendments, such as the First Amendment. Prior restraint, which deals with the possibility of an unfair jury due to media coverage, and jury nullification, which means the jury says the defendant is innocent despite feeling otherwise, both make the Sixth Amendment unclear.