Criminal charges against an embattled former Tisbury police officer have been dismissed.

Last Friday in Edgartown district court all charges were dropped against Kelly Kershaw, 31, a former police officer who has been involved in more than one public dispute with the town and police. In district court Ms. Kershaw had been charged with interfering with a firefighter, assault and battery on a police officer, disorderly conduct and threat to commit a crime after an incident during a May fire at her Vineyard Haven home.

All four charges were dismissed on request of the commonwealth with Ms. Kershaw’s consent.

Cape and Islands assistant district attorney Kerry Whalen told the Gazette Tuesday that after a review of the alleged evidence, information from the defense counsel and discussions with the Tisbury police chief, the office “decided that [dismissing the charges] would be the best course of action for everyone involved.”

Former Tisbury police chief Theodore A. (Teddy) Saulnier, now a lawyer, represented Ms. Kershaw in the criminal case. Reached by phone Tuesday, he said “the parties reached an amicable settlement.”

Ms. Kershaw had been employed by the Tisbury police department since 2004. She had been on administrative leave since November of last year following an incident where she was the driver in a one-car crash in town. Alcohol and texting were not factors in the crash.

In June, the Tisbury selectmen voted unanimously to fire Ms. Kershaw. At the time, her attorney, Jennifer Smith, told the Gazette that Ms. Kershaw should not have been fired and she would take action toward reinstatement.

Tisbury selectmen met with Ms. Kershaw and Ms. Smith during an executive session meeting three weeks ago. Ms. Smith told the Gazette Tuesday that the matter has been resolved to the mutual satisfaction of both parties.

The resolution brings to an end a long history of proceedings between the town and Ms. Kershaw. In 2009, Ms. Kershaw filed a complaint with the Massachusetts Commission Against Discrimination (MCAD), claiming that she had been sexually harassed by a fellow officer and that retaliatory action was taken by the police chief and town administrator when she complained about the harassment.

In September 2011 an MCAD investigation found probable cause for some of the complaints in a split decision.

Ms. Kershaw later withdrew her complaint and the case was dismissed and no further action was taken by MCAD.