Approximately a year ago an elderly gentleman who was my best friend was attacked and beaten in his home and he passed away as a result.  At the beginning of the police investigation back then I was questioned and requestioned (resembled Nazi interrogation with scare tactics, threats, badgering, confusion tactics, the whole nine yards)  I have no idea what happened to my friend. I was very shocked at what happened to him and very grief-stricken at his loss, a grieving process which I was not allowed to go through due to the police interrogations.  I am a 49 yr old registered nurse who can barely kill a fly and completely non-violent.  I abhor any kind of violence.  It is very upsetting to me to even discuss it.  The police have never been able to figure out who did this to my friend.  I was the person who knew him best and who was closest to him.  I guess they want to solve the case and who better to shove it off onto than me, who can not even defend myself.  A couple of days ago a sheriff's detective and a detective working with the FBI in the State Police Dept. came to my house to inform me that they had arranged a polygraph test for me this coming thursday and they would be here to pick me up Thursday morning to take me to the city (far away) where the polygraph test would be administered.  A year after my friend was murdered.
I know nothing about what happened to my friend.  I can barely remember the sequence of events from a year ago.  Any time my friend's name or what happened to him is mentioned, it upsets me very much.  During previous questioning they told me I was a "suspect".  I am very scared that they are trying to shove this off on me because they can't find who really did it.
What should I do????

It is ok to email me.  I need help.  I have heard of a lot of people who have been falsely charged and convicted of crimes they did not commit.  This is very serious.  I don't know who beat my friend, but it certainly was not me!!!!!
 
Please help.

Thank you very much for your reply to my post.  I barely slept at all last night.  I tend to agree with you that it is probably a tactic to try to browbeat a confession out of someone.  Elections for a new sheriff here are in November and the person at the head of this investigation is the Democratic nominee for the office.  "solving" this case would be very helpful in ensuring his election.  They don't care if they get the right person or not.  As long as they say they solved it.  I did place a call to a highly regarded lawyer in this area this morning.  He is at court and I should be able to reach him by 11:30 this morning.  My big problem is this:  I am very poor. To make matters worse, I had a bad car accident a week ago with severe chest injuries so I will not be able to go to work for about 6 weeks.  Lost my car, etc.  I have no money whatsoever to pay a lawyer with.  Is any lawyer going to take me under these circumstances???
I am in excruciating pain right now and I don't know if I could even make this 2-3 hour trip they are talking about.  I can barely walk.
Please let me know if a lawyer will take me.
ava

MagicStarER,

Please check your private messages on this board.

I shared everything I possibly knew about my friend with the authorities a year ago at the beginning of the investigation.  I simply do not know any more than that.  I do not know what happened to him.  I was not there.  I have nothing else to tell them.  I did speak to the highly-regarded lawyer I mentioned. He advised me to tell them I would give no more statements nor take a polygraph without a lawyer being present.  He said that polygraph results are not admissible in court, nor is the refusal to take a polygraph test admissible evidence.
He said I need a lawyer now.  He charges a $2500 retainer fee.  (out of the question absolutely, for me).  I'm sure my refusal to take the test will anger them.  I am very frightened.  But I must defend my innocence and my person.  I will not be harassed for something I had nothing to do with.
It is just a question now of what they decide to do next.

I would like to thank you all very much for your replies and your insight.  I did tell the detective from the sheriff dept that after researching polygraph testing and speaking to a lawyer, I had decided to give no further statements nor submit to any polygraph testing without a lawyer being present, and that I had already helped them with everything I knew a year ago and had nothing additional to add.   
I am very frightened by all of this.  I feel like I am under a microscope and that I am being totally misjudged.  I am no way a violent or revengeful person.  I am a very quiet, tolerant peace-loving person.  I have never hurt anyone in my life.  I feel that the only reason they are focusing on me is because I was the person who was closest to the victim.  It is very frightening to find yourself being looked at as a potential crime-perpetrator when you know that you had nothing whatsoever to do with it.  And when you have no financial means to protect yourself, it is doubly scary.  I very much appreciate all of your consideration and the time you have taken to read my post and to answer it.  I may be helpless economically, but I am no dummy and I have no intention of being harassed or browbeaten into saying that I did something that I did not do - I don't care if they kill me, I will not do this.  I already know that I am not a good polygraph subject - I have high blood pressure, and right now extremely painful chest injuries that cause a stress reaction every time I even move.  Also, losing my friend to a violent crime was very traumatizing to me and any time I think about him and what happened to him I become very upset.  He was my friend and like family to me.   
So I thank you all for your time.
I will keep you posted on what happens next.

As for lawyers, you can not retain a public defender in this state unless you have been charged with a crime and the defender is appointed by the judge, so looking for a public defender is premature.  I hope it does not get to that point.  Because I know I had nothing to do with it, and because I know that there is no evidence against me, because that would be impossible, because I was not there and had nothing to do with it.   
But like the lawyer said, plenty of people have been charged with and convicted of crimes they did not do with no evidence.   

To the person who said "innocent until proven guilty".   I don't believe that exists any longer in this country.  I believe it's more like:  "You are guilty because we said you are, we will make sure there is no way you can defend yourself, and the only thing you can do is play "let's make a deal" in the courtroom"  There is no longer any justice in this country.  Whoever believes that there is, is under a delusion.