How are people protected under the 6th Amendment?
The Sixth Amendment guarantees that someone accused of a crime (1) has the right to a prompt, public, trial, (2) the right to a lawyer, (3) the right to an impartial jury, and (4) the right to know the people that accuse someone of a crime.
The Sixth Amendment protects people in several ways, I'll list them below:
The right to a prompt, public, trial
A prompt trial prevents someone from unlawfully being detained and from being detained indefinitely. A public trial prevents any malfeasance (or wrongdoing) by any of the parties involved in the trial (the judge, the defense, the prosecutors, or the jury), the public would perceive any wrongdoing as an injustice and call for a retrial or to have the ruling overturned.
The right to a lawyer
A lawyer is someone who knows the law. Having an experienced professional handle someone's court case can prevent the defendant from unjust treatment or self-incrimination (lawyers know how to present a case without making the defendant look like a heartless person).
The right to an impartial jury
The jury determines the verdict (whether the defendant is guilty or innocent), if the jury were partial to the prosecution they jury would be more likely to find the defendant of a crime (it eliminates bias, ensuring that the verdict was only based on the evidence presented in the courtroom).
The right to know one's accusers
This essentially ensures that the defendant can cross-examine (question) the witnesses or their accuser in an attempt to challenge their testimony. If the witness or the accuser's story changes when they are questioned a second time their credibility can be called into question (if someone changes their story, at least one of the stories is a lie).
I hope this helps!