Defenses to Crimes

Customized Legal Defense to Crime

Let the Law Office of Patrick J. Murphy construct and tactically employ a winning legal defense strategy that is custom made to your particular situation. Every case is different with its own witnesses and evidence. Although law professors like to instruct first year law students that a defendant on trial may sit back and put the prosecution to its burden to prove the charges beyond a reasonable doubt, important legal defenses must be raised and argued to the judge and jury in a forceful, competent and effective way. Although our system of justice requires nothing from the defendant who enjoys the presumption of innocence, when criminal behavior falls within an exemption or exception to the criminal law, a defendant may be required to proffer some evidence that the conduct under the circumstances is excused by asserting an affirmative defense to the crime charged.

The Law Office of Patrick J. Murphy is fully cognizant of every defense to crime recognized by our legal system and has experience in asserting the criminal defenses including but not limited to:


If a defendant’s action is due to an accident, the action is not criminal under Massachusetts law. For an action to be criminal, it must be intentional. When the defense of accident is properly raised, and where there is relevant evidence presented, a just must instruct the jury that the prosecutor has the burden of proving beyond a reasonable doubt that the conduct alleged was not accidental.


An alibi defense exists if there is evidence which tends to prove that the accused did not commit the crime because he was actually somewhere else at the time of its occurrence. Since it is impossible to be two places at the same time, such evidence negates the possibility that the defendant committed the crime. In Massachusetts, a defendant may be compelled to disclose his intention to rely upon an alibi defense. The defendant asserting an alibi defense must disclose the names and addresses of his alibi witnesses. In turn, the prosecution must also provide the defense with the names and addresses of those witnesses that will testify to place the defendant at the crime scene.


Most States and Federal courts recognize the defense of entrapment and this is also true of Massachusetts courts. Entrapment exits where law enforcement officials plant criminal ideas in a person’s innocent mind and, as a result, bring about the commission of a crime by an individual who otherwise would not have engaged in the criminal activity. The government cannot tolerate its law enforcement officers, who are sworn to uphold the law, to initiate crime by planting criminal ideas in innocent minds. The defense of entrapment is often raised in cases where the police use undercover officers and agents who employ strategies to set traps for innocent persons not inclined to commit crimes until pressured by undercover law enforcement. Where there is evidence that the conduct of the undercover officer involves arguing or pleading with a defendant then there is evidence of entrapment and the burden is on the prosecutor to prove beyond a reasonable doubt that the defendant was actually predisposed to commit the crime charged.

No Identification

In a criminal case, there must be proof beyond a reasonable doubt the person charged was the same person that was observed committing the crime. Identifying the defendant as the perpetrator of the crime is fundamental to the criminal process and the ability to move forward with a criminal prosecution. If there is no identification of the defendant by a witness, then there can be no conviction in the case. Unfortunately, there is ample opportunity for a mistaken identification or an unfair identification procedure before the before trial or at trial with the use of line-ups, photo arrays or one-on-one show-up identifications. In Massachusetts, experienced and aggressive defense counsel will protect a client from unfair procedures by filing a motion to suppress the identification since it makes it very difficult, if not impossible, for the jury to determine if the defendant was the actual perpetrator of the crime under certain circumstances. Indeed, the danger of mistaken identification is widely recognized and is a primary cause of erroneous convictions.

Intoxication With Alcohol or Drugs

Intoxication has been defined as a disturbance of a person’s mental or physical capabilities resulting from the excessive intake of liquor or drugs. In Massachusetts the law is that where proof of a crime requires evidence of a specific criminal intent and there is evidence in the case to show that a defendant was under the influence of intoxicating liquor or some drug at the time of the offense, then the judge may give a jury instruction that the jury may consider evidence of the defendant’s intoxication at the time of the crime in deciding whether or not the prosecution has proved the element of specific intent beyond a reasonable doubt.

Lack of Criminal Responsibility (Insanity)

The condition of a person’s mind at the time of the commission of a crime or at any stage of the criminal proceedings is of utmost importance under Massachusetts law because it determines whether or not a person is legally responsible for the crime or whether the individual is even competent to stand trial. In Massachusetts a person is not responsible for criminal conduct if at the time of such conduct as a result of mental disease or defect that person lacks substantial capacity either to appreciate the criminality (wrongfulness) of his conduct or to conform his conduct to the requirements of law. The burden of proof on the issue of insanity falls upon the prosecution which must establish all elements of the crime and the defendant’s mental capacity or ability to form the requisite mens rea for the crime. In Massachusetts, a jury may also consider the effect of a defendant’s involuntary mental illness or his capacity for deliberate premeditation.

Mental Impairment Short of Insanity

For mental impairment that does not rise to the level or insanity (lack of criminal responsibility) Massachusetts for the mental condition to be considered by a jury on the issue of whether or not a defendant had the necessary criminal intent that is required for a conviction of the offense charged. Mental impairment short of insanity applies in situations where a specific intent is a necessary element of the offense. A defendant cannot be found guilty without that intent. The jury may take into account in its deliberations any evidence about the defendant mental condition. If a defendant is not capable of having the necessary intent to commit the offense, that defendant must be acquitted.

Necessity or Duress

Massachusetts recognizes the defense of necessity and it exonerates the defendant in circumstances where the offense committed was out of necessity to avoid a greater harm or evil than would be caused by the commission of the crime that the defendant has been accused of. The prosecution must prove beyond a reasonable doubt that the defendant is not entitled to claim the defense of necessity. The following conditions must be met for the defense of necessity to be available to the defendant: The defendant was confronted with a clear and imminent danger; the defendant reasonably expected that his actions would be effective to reduce or eliminate the danger; that there was no legal alternative that would have been effective to eliminate or reduce the danger.

Self-Defense; Defense of Another; Defense of Property

In Massachusetts, a person may use “reasonable force” to protect himself from harm. That person may also use “deadly force” if he or she has reasonable grounds to believe and did believe that he or she was in imminent danger or death or serious bodily harm at the time of the incident. A person may also use force against another to protect a third party provided there is a threat of harm to the person being protected. A “reasonable person” standard is applied to determine if the force used was necessary to protect the third party. Moreover, an individual also has the right to use reasonable force to protect either real or personal property, however, the use of deadly force is prohibited to protect any property. A defendant in a criminal case is entitled by law to a jury instruction on self-defense in Massachusetts if the evidence is sufficient to raise the issue. Patrick J. Murphy, Esq. is a Boston, Massachusetts self-defense criminal attorney with years of experience defending those accused assault crimes.

Boston Criminal Defense Lawyer Blog - Self-Defense
Client Reviews
"Highly Recommended. Attorney Patrick J. Murphy absolutely helped me out in my time of need. When I met him in his Boston office he put me right at ease and explained the criminal process to me in a way I could easily understand and in a manner that gave me complete confidence. I was facing a criminal wanton destruction of property charge in Barnstable District Court. On the day of the case, he was at the courthouse waiting for me and my wife. Mr. Murphy handled the hearing in a very thorough and professional manner putting us through our testimony and making a powerful argument to the decision maker. My case was thrown out and I could not be happier with the service from Attorney Murphy. I highly recommend him to you as a skilled legal advocate!" Rob, Avvo User
"Excellent Criminal Defense Lawyer. From the first consultation I knew Patrick Murphy was the right choice for my criminal defense. He was knowledgeable of the laws and knew how to build up a strong defense for my case. Every phone call and email I made was promptly answered. When it came time for my hearing, Patrick was prepared and able to get the criminal complaint against me dropped without ever becoming charge! Would highly recommend this attorney to anyone seeking a top quality defense attorney to handle their case!" John, Avvo User
"OUI Not Guilty Verdict. Patrick Murphy provided excellent service as council on my case. He worked diligently over a long legal process that spanned over 3 years. He was able to take my case to a Jury Trial and get me a Not Guilty verdict through he expert knowledge of the law and expertise in cross examination of the prosecutions witnesses. He was very professional and available at anytime night or day to answer questions." Chris, Avvo User
"Highly Skilled and Professional Lawyer. Attorney Pat Murphy did a great job guiding me through an A&B charge, and most importantly getting the case dismissed in a very timely manner. He is very professional, returns call promptly, and did a great explaining his strategy and the legal process to me. I was confident throughout the whole process that I was in good hands and would receive the best possible outcome in my case. Would highly recommended Attorney Murphy." Avvo User
"I Felt That I was in Good Hands... and I Was! Mr. Patrick J. Murphy was very quick to respond to my needs. He was always there to answer any questions I had in a timely fashion, and he made me feel very comfortable in an extremely uncomfortable situation. Having Mr. Murphy by my side in the courtroom felt like I was at an advantage. He speaks with confidence. He doesn't stutter or pause while put on the spot. He treated me with respect. He listens. He always greeted me with a warm welcome and never wasted any time." Avvo User