The short answer is YES, a person can be charged based for a felony based on hearsay, even without past criminal history. An indictment or information need to be based on "probable cause," which essentially means "is it even slightly more likely than not that a crime was committed, and that this person committed it?" Indictments are issued by Grand Juries, who are ordinary citizens given only parts of the story, by prosecutors and law enforcement officers, usually without any defense witnesses. The alternative process is by way of Preliminary Hearing: again, a very short process with limited witnesses, often preempted by an indictment, and only requiring "probable cause." The proof required at a TRIAL is "proof beyond a reasonable doubt." That is where hearsay is put under the microscope and torn apart. Past criminal history at trial is allowable under certain circumstances, for example, if it is recent enough (considering the date that the sentence ended, not the date of the crime) and if it helps show motive, absence of mistake or accident, etc.
Your question assumes that the charge is based only on hearsay and past criminal record. You do not know, and may never know for sure, what other reasons are behind it. There could be a confidential informant who is telling the truth or telling lies; there could be an eyewitness who saw something which they reported but which they misinterpreted as criminal activity when, in fact, it was not; there are many ways of being wrongly accused. Wiretaps require the prior approval of a judge. Law enforcement can watch you, and follow you around, anytime you are outside of your own home. As long as they do not substantially interfere with your activities, and can articulate some kind of suspicion about criminal activity, winning a harassment claim would be almost impossible. If you have already been charged, you need to start working with a lawyer immediately. If you think you are on the verge of being charged, hiring a lawyer would be very smart. A lawyer can request the opportunity to present defense evidence to the grand jury before the are given a chance to hear the prosecutor's evidence and vote on whether or not they believe there is probable cause to indict you. That lawyer can also give you other advice and collect evidence that might not be available after more time passes. Good luck.
There are two ways a person can be charged, either directly by the prosecutor or by Grand Jury Indictment. The general standard is that there is probable cause the person committed the charged crime. The state always holds the burden beyond a reasonable doubt to prove the person committed the crime. That is where good lawyers come into play. Youo should make sure the person has a lawyer who can look at the situation and the facts and make sure the person has the best defense.
My two colleagues have given you excellent answers. If you have just recently been indicted, then you probably know precious little about what the "evidence" really is against you. Your lawyer will be paying close attention for when the Grand Jury transcript is filed so that she can obtain a copy of it and see if any challenges to the Grand Jury proceedings need to be made. The rules only allow 25 days from the time it is filed.
Regarding the issue of prior felony convictions: there is a lot that can be said about this, but the main thing is that, as my colleague noted, they can be used as historical priors to elevate a person into a higher sentencing category, based on the age and nature of the convictions. Some convictions are "forever priors" such as Aggravated DUI and various sex crimes and homicides. Some have ten year and five year cutoffs, which start from the date the sentence expires, or when a defendant "kills his number" not when the crime was committed. Moreover, one must be acutely aware of the fact that the police are trained to put more focus on an individual with a past criminal history. The reasons for this can be debated, and I don't think they would ever freely admit that they do that. But, I think it probably has a lot to do with the simple fact that a person with prior felony convictions is "low hanging fruit" compared to a person with a clean record. By this, I mean to say that a person with a prior criminal record is much easier to convict again. Why? Because, under most circumstances, if a person with a prior record testifies, the prosecution gets to bring up their past convictions in front of the jury. This is called impeachment under Rule 609 of the Rules of Evidence. Most of the time, when a jury hears about the defendant's prior convictions, they immediately decide that he is guilty. So, simply put, a person with a criminal record is easier for the police and prosecution to convict again. Not only that, but you have to keep in mind what their mind set is. They do not believe in redemption. Individuals might, but the institution of the criminal justice system is cold and harsh.
I'm adding some links at the bottom of this for more information on some of these rules and laws.
I'm afraid you will need to find a lawyer as soon as possible and only work with and speak with her about this.
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