By this time Peterson was so burned out on the politics of downtown that he transferred to the remote East San Diego substation where he quietly went about his business for the next few years.

When George Sears was fired in late April 1939, Peterson knew he would be considered for the replacement job so he quickly retired.

In his place Chief of Detectives Harry J. Kelley was appointed acting chief while the City Manager tried to talk John Peterson out of retirement. The manager finally managed to convince Peterson to take the job so on July 19, 1939, Harry Kelly was replaced.

John Peterson would remain at the helm until March 16, 1940, when Lieutenant Clifford Peterson (no relation) of the Long Beach Police Department was hired as the permanent chief. After his final demotion in 1940, John T. Peterson called it a career once and for all.

John T. Peterson died in 1947.

John T. Peterson was a career San Diego police detective however he will probably best remembered for being sworn in as the Chief of Police on three different occasions. All stints as chief were short and only once was he officially considered chief. The other two times he was the interim chief of police.

Peterson was first hired as an SDPD officer in 1912.  After a short time in patrol, he was promoted to detective and was in the bureau as a lieutenant when he was made temporary chief on June 12, 1932. His appointment came when Chief Harry Scott suddenly resigned after only ten months in office. Peterson was at the helm for less than 60 days when he was replaced by a permanent chief Robert P. Newsom.

Peterson went back to Detective Lieutenant as both Chief Newsom and his successor, Chief Harry Raymond, served abrupt terms. Without a clear selection for a successor, the City Manager reappointed John Peterson as chief - this time permanently.

Peterson served a little more than a year - September 2, 1933, to September 6, 1934 - and did a good job however he made it clear to the council he didn’t like the politics of the office and they should appoint someone else. So on September 7, 1934, Detective Lieutenant George M. Sears was appointed as the permanent chief.
06/12/1932 - 07/31/1932 & 09/02/1933- 09/06/1934
& 07/19/1939 - 03/20/1940