私も警察の人に6ヶ月とはっきり聞いたんですが、Application for permanent Residence Federal Skilled Worker Classの中に
Certificates must be originals and issued within the last three months. と3ヶ月と書いてあったので、念のために、3ヶ月以内のものを出しました。
Security requirements
Police certificates and clearances You and your family members must provide us with a police certificate issued by the authorities of each country in which you have lived for six (6) months or more since reaching the age of 18. Certificates must be originals and issued within the last three months.
If you have been convicted of a criminal offence in Canada, your application cannot be approved unless you receive a pardon. To avoid the unnecessary payment of processing fees for an immigration application that will be refused, you should first apply for a pardon to the: