No, you can not be arrested based on somebody's signed statement.
Judges must issue warrants based on probable cause, NOT heresay.
The story you relate is, indeed, a result of probable cause,
based not on your stupid friend's signed statement,
but that pound of pot the cops confiscated from him.
WTF? Not another one.....
We were arrested for the weed based on the one persons statement. The same statement was also used to obtain a warrant to search our homes and vehicles......