SANTA ANA, Calif.—A 69-year-old man was sentenced this week to a year in jail for taking lewd photos of a girl at a beach in Newport Beach and a year later assaulting three other girls.

Joel Evan Shankman pleaded guilty Oct. 6 to four counts of annoying or molesting a child younger than 18 with a prior conviction, attempting to use a minor to perform sex acts, all felonies, and a misdemeanor count of sexual exploitation of a child, according to court records. He was sentenced Dec. 6 to a year in jail and two years of formal probation.

According to testimony in the defendant’s preliminary hearing, police said a witness saw the defendant at the 28th Street beach taking cell phone photos of the girl at the jetty Aug. 28, 2018. He had introduced himself to the girl’s mother as a junior lifeguard, police testified.

According to court records, Mr. Shankman admitted that he was previously convicted of child annoyance of a 5-year-old girl on Nov. 16, 1995, in Orange County.

Mr. Shankman admitted in his plea deal that he attempted to “persuade and induce Jane Doe, a child under the age of 18 years, to engage in modeling or posing for purposes of preparing a photograph involving sexual conduct by Jane Doe.”

Mr. Shankman also admitted child annoyance involving three other girls on July 9, 2019, according to court records.