Can detectives still question me if I have been served a subpoena?

Yes.

If you have been served a subpoena the both the defense and the prosecution will want to interview you. You do not have to answer any questions by either side.

Here is the advice I give people in this situation. I tell them to say to the detective: "I will be happy to talk to both the Prosecutor and the Defense Attorney, together, so they both know what I will testify to. If you don't want to do this then you can find out what I have to say when I am on the witness stand, under oath, so both the prosecutor and defense lawyer will learn it at once". You do not have to talk to them and if they harrass you let the defense attorney know what they are doing. They tend to be bullies if they feel you aren't smart enough to stand up for your rights.

You can either speak to them or not. If there is any possibility that you could incriminate yourself by doing so you should not. To be on the safe side, you should consult with a criminal defense attorney before making any statements to the police, especially if you are concerned about some potential involvement. You do, however, have to respond to the subpoena, which means to show up to court on the date and time and place listed on the subpoena.

You never have to answer law enforcement questions other than requests for identification purposes (e.g. "What's your name?"; "Where do you live?"). You don't have to answer any questions from anyone unless you are compelled to take the stand by a subpoena. So, until you are on the stand, and have sworn to tell the truth, the whole truth and nothing but the truth, you don't have to answer anything. Yes, I would definitely consult an attorney to ensure your rights are protected.

Of course they can question you. You can refuse and tick them off, as long as there is no risk of you being charged with any crime. If there is any risk, then see below. Whenever threatened, arrested or charged with any crime, what can you do? No amount of free 'tips and hints' from here or anywhere else are going to effectively help you in your defense, other than the advice [if not already too late] is to exercise the 5th Amendment RIGHT to SHUT UP and do NOT talk to police or ANYONE about the details of the case except through an attorney. That includes on this or any other web site or public forum. Most police and prosecutors will happily tell you that 95% of people convict themselves by trying to be 'helpful and cooperative', either during initial contact, questioning, interview or interrogation. Hire an attorney, unless you know how to effectively represent yourself in court against a professional prosecutor intending to convict.

NO! YOU DO NOT HAVE TO TALK TO THEM. IF THEY ARE TRYING TO TALK TO YOU, BE VERY CAREFUL, THEY MAY BE TRYING TO SET YOU UP TO IMPLICATE YOU IN THE UNDERLYING CASE THAT IS BEING PROSECUTED. ALSO, IF YOU ARE IN POSSESSION OF ANY INFORMATION THAT MAY REMOTELY TIE YOU INTO THIS OTHER CASE, YOU CAN REFUSE TO TESTIFY ON CONSTITUTIONAL GROUNDS. FINALLY, YOU SHOULD SERIOUSLY CONSIDER RETAINING A PRIVATE DEFENSE ATTORNEY TO PROTECT YOUR RIGHTS IN THIS SITUATION, NO MATTER HOW INNOCENT YOU THINK YOU MAY BE. ONCE YOU OPEN YOUR MOUTH TO THE DETECTIVES OR ON THE WITNESS STAND, IT WILL BE TOO LATE TO TURN BACK THE CLOCK!

You absolutely DO NOT have to answer questions. The only reason they are doing it is to impeach you later in court if you don't testify the way they would lilke. Remember, whatever you say ends up getting twisted around to suit their purpose. And yes, you should definitely contact an attorney before you do something foolish and incriminate yourself.

Generally you do not have to speak with detectives if you do not want to speak with them. To be safe it would be a good idea to speak with a criminal defense lawyer.