Many states have laws that place specific duties on law enforcement officers who investigate allegations of domestic violence. State laws also protect officers who perform domestic violence investigations from being charged with a crime or being sued by suspects, victims, or witnesses. Although state legislatures have created laws giving officers immunity from civil suits and criminal charges, the protections provided by these statutes are not absolute. As explained below, law enforcement may be subject to civil suits and criminal charges under certain circumstances.
While police officers frequently arrest persons suspected of committing crimes, not every offense requires the arrest of the suspect. The law varies from state to state, but for minor offenses officers may have the discretion to issue a written citation to a suspect in lieu of arrest.
In domestic violence investigations, however, officers in a number of states are required to an arrest a person suspected of committing domestic violence under certain circumstances. For example, Arizona law requires the arrest of assailants suspected of inflicting physical injury or discharging, using, or threatening to use a firearm. When a domestic violence offense does not involve physical injury or a firearm, officers are not required to make an arrest. (Ariz. Rev. Stat. § 13-3601.)
Although some states require that a misdemeanor be committed in the presence of an officer in order for the officer to make a warrantless arrest, several states like Louisiana authorize the immediate arrest of a persons suspected of committing domestic abuse, even if the officer did not witness the abuse. In Louisiana, officers who suspect domestic abuse must immediately take all reasonable steps to prevent further abuse, including making an arrest of any family member, household member, or dating partner suspected of committing any felony or a misdemeanor that endangers the victim's personal safety. (La. Rev. Stat. § 46-2140.) In Minnesota, an officer must arrest anyone whom the officer has probable cause to believe has committed domestic violence, and must also arrest those who have violated protective orders; these arrests may be accomplished without a warrant. (Mn. Stat. Ann. § § 629.341, 518B.01(e).) In Montana, officers must arrest an assailant if the assailant injured the victim, used or threatened to use a weapon, or violated a protective order (an officer who does not make an arrest must file a written report that explains why no arrest took place). (Mt. Code. Ann. § § 46-6-311, 46-6-601, 46-6-603.)
Officers may also be prohibited by state law from taking certain actions when investigating domestic violence allegations. Alabama law, for example, forbids an officer from threatening to arrest everyone involved in a domestic violence complaint for the purpose of discouraging the victim from asking for police assistance. The statute also prohibits an officer from basing the decision to arrest on the victim's permission or request, nor can the arrest decision be based on a victim's or witness's willingness to testify in court. (Ala. Code §13A-6-134.) Other states have similar statutes that prohibit officers from taking actions that might hinder or block an appropriate investigation and prosecution of domestic violence offenses.
In addition to imposing duties upon officers conducting domestic violence investigations, state laws also provide officers with protections from civil lawsuits and criminal charges. These protections are not simply defenses that the officers may raise after they're charged or sued—they effectively prevent a criminal charge or civil lawsuit from going forward.
For example, Arkansas law provides that "any law enforcement officer acting in good faith and exercising due care in making an arrest for domestic abuse…shall have immunity from civil or criminal liability." (Ark. Code § 5-53-134.) This means that an officer who is criminally charged or named in a civil lawsuit need only establish that he acted in good faith and exercised due care, regardless of the validity or outcome of the arrest. If the judge is convinced, the prosecution or lawsuit will be dismissed.
Similarly, Colorado law protects officers from both civil lawsuits and criminal charges as long as the officer acts in good faith. (Colo. Rev. Stat. § 18-6-800.3.)
Although both the Arkansas and Colorado statutes provide civil and criminal immunity to officers who make domestic violence arrests in good faith and for good cause, an officer who makes an arrest in bad faith (for example, arresting the suspect based on a personal vendetta) loses the protection provided by the laws. This officer may have to answer to a criminal charge and a civil suit. This means that an officer who normally would be one of the prosecutor's main witnesses in a domestic violence prosecution might instead find himself charged as a defendant in a separate case and have to defend against allegations of improper or even illegal conduct. As for the original case against the domestic violence suspect, the prosecutor may decide to make a favorable plea offer or even dismiss the case if the officer's conduct was particularly questionable. So, while officers will normally be protected from a lawsuit or criminal charges, arrests based on an officer's maliciousness or other improper motive may cause the officer to lose those protections.
Although a law enforcement officer may be immune from being sued or from being criminally charged in state court for failing to perform duties imposed by state law, an officer may nonetheless be sued in a federal civil suit if the performance or failure to perform duties imposed by state law results in a violation of a person's federal constitutional rights.This is possible because federal law, specifically 42 U.S. § 1983, allows a person to sue a police officer or other government official who violates the person's civil rights.
"Section 1983 lawsuits," as they are known, are based on the Civil Rights Act of 1871, which aimed to stop illegal post-Civil War racial activities taken mostly by the Ku Klux Klan and ignored or treated lightly by state prosecutors. One of the most famous "1983" civil suits involved the 1991 beating of Rodney King after the Los Angeles riots. Officers involved had been acquitted in a state court criminal case, but two of the four were found to have violated King's civil rights in the subsequent federal lawsuit.
You may wonder how it is that an officer can be sued in federal court, under a federal law, for the same act that resulted in an acquittal in a state court. The answer lies in the fact that the federal government is a separate "sovereign" from the states, which allows Congress to charge and prosecute someone even though the state has done so already.