Thomas Dale presided during times of tragedy

Notable dates during the tenure of Nassau police Commissioner Thomas Dale:

Jan. 2, 2012: County Executive Edward Mangano appoints Dale, NYPD's chief of personnel, as acting commissioner for a police force beset by problems. Fresh on the new commissioner's agenda: investigation of a New Year's Eve Seaford pharmacy robbery in which a retired Nassau cop fatally shoots an ATF agent by mistake.

February 2012: New rules on tighter control of crime scenes implemented after Officer Geoffrey J. Breitkopf is accidentally shot to death by an off-duty MTA officer in March 2011.

Feb. 27, 2012: County legislature delays confirmation of Dale -- some Democratic lawmakers say they don't like him.

March 1, 2012: Three former high-ranking officers are indicted on conspiracy and misconduct charges stemming from a May 2009 school burglary in which they allegedly prevented the arrest of a police benefactor's son for the crime.

March 5, 2012: County legislature confirms Dale as commissioner and approves merger of the county's eight precincts into four.

May 2012: Precinct mergers begin.

June 18, 2012: Mangano signs legislation broadening police commissioner's authority to discipline officers.

July 2012: Fifth Precinct's new commander, Thomas DePaola, boasts of dramatic crime drops, but an internal investigation alleges he falsified about 18 months of crime figures, including at the Sixth Precinct.

July 31, 2012: Internal Affairs Unit reports that off-duty officer unlawfully shot and beat an unarmed cabdriver in Huntington Station in 2011. The report recommends 19 departmental charges for what it found to be 11 unlawful acts and eight departmental rules violations.

August 2012: Nassau County launches police recruitment drive.

August 2012: Three Nassau residents sue Dale, contending the department failed to process their pistol license applications within the legal time frame.

September 2012: The Nassau Police Benevolent Association files case challenging Dale's disciplinary authority, saying union contract calls for disputes to be settled by independent arbitrators.

Oct. 23, 2012: Department is rocked by back-to-back deaths of officers -- Joseph Olivieri, struck by an SUV while at an accident scene on the Long Island Expressway, and Arthur Lopez, shot to death by an ex-convict while investigating a carjacking.

Dec. 15, 2012: Former Nassau police Officer Michael Tedesco is arraigned on a 108-count indictment alleging he spent at least 80 of his shifts with his mistresses instead of covering his beat.

April 17, 2013: Nassau's Police Benevolent Association says precinct mergers led to crime spikes.

May 17, 2013: 37 recruits are sworn in as Nassau police officers.

May 17, 2013: Nassau police officer accidentally shoots and kills Hofstra University student during a home invasion just outside the campus. The officer also fatally shot the suspect.

May 18, 2013: Dale goes to the student's Westchester County home to offer "my most sincere and heartfelt condolences."

August 2013: Andrea Rebello's family files notice of intention to sue police, county.

October 2013: County wraps up retesting of criminal evidence at the police crime lab, shuttered in 2011 due to evidence-testing mistakes.