To unlock the Cleaning Up Seconds trophy in American Fugitive, you will need to knock out 5 people with a toilet brush.
You can find a toilet brush by breaking into a residential property and heading to the bathroom upstairs. Once you have the toilet brush, head to a highly populated area such as a park, car park etc. Equip the toilet brush and smack away until you knock out 5 people.
If the time is an issue, upgrade your melee attack so that it makes it easier for you to knock people out.