But police say parents can still contact them if they are concerned that their daughters were among dozens of unidentified young girls Lewsam filmed at Lakeside Joondalup or Warwick Grove between 2012 and January this year.
The 50-year-old offender used a phone camera or GoPro device to record himself abusing children in the toy sections of shopping centre outlets. Officers seized footage of 78 children, but the identities of 77 of them remain unknown.
Given the footage allowed police to land a conviction against Lewsam without the victims� identities, Sex Assault Squad Sergeant Rob Witt said police were not �actively looking to identify unknown victims� now the case had ended.
But he still encouraged parents to contact police if they were concerned.
�Due to the insidious nature of Lewsam�s offending and the apparent young age of the victims, many children would be unaware or may not be able to recall or articulate the offending,� Det-Sgt Witt said.
�If parents have specific concerns their female children under the age of six years may have been offended against at the Warwick or Joondalup shopping centres in the last three years, they could contact the Sex Assault Squad to discuss those concerns.�
Lewsam was sentenced in the District Court on July 30 to more than 16 years in jail for more than 120 offences, including sexual penetration of a child under 13 years.
In light of the incident, Det-Sgt Witt offered general advice for parents.
�Police recommend in general that if parents or carers of young children have any concerns regarding suspected child protection matters they should contact their local Child Protection and Family Services office,� he said.