Lansdowne, 69, announced he was stepping down in the wake of a mayoral election and a rash of allegations of misconduct by SDPD officers.
Lansdowne declined to elaborate on his reasons for retiring when contacted by reporters. He told the San Diego U-T in a written statement he "truly values the citizens of this city and the employees who work here."
Mayor-elect Kevin Faulconer told the U-T he had not pressured Lansdowne to resign, although he told the newspaper's editorial board on Monday, "There is absolutely a need to make sure we have public trust and confidence in the San Diego Police Department." He added "I will be taking definitive steps to make sure that happens."
Lansdowne, who was chief of police in San Jose from 1998-2003, enjoyed a relatively stable tenure in San Diego; however, the department recently had to take action against some of its own officers.
On Tuesday alone, a veteran detective was arrested for suspicion of drunken driving when she was discovered sacked out in her car, and a former officer was cleared on sexual battery and bribery charges due to a technicality.
In another case this month, an officer resigned after being charged with sexual battery and false imprisonment by four women he came in contact with while on duty.