I was looking at the roommate being responsible for damage caused to property entrusted to the care of ibnatasha2u. ibnatasha2u has a security deposit at stake if the property is not returned to the landlord in the same condition it was in when rented, minus normal wear and tear.
RCW 59.18.130:
https://apps.leg.wa.gov/RCW/default.aspx?cite=59.18.130
Perhaps seemingly so, but only ostensibly so as your layman's reasoning ignores and fails to treat with the following unassailable facts:
1. That the primary purpose of the standardized rule of law (federal and all state courts alike) demanding that
all actions must be brought in the name of the real party interest is the avoidance of multiple lawsuits over the same subject matter and affecting the same parties.
2. That here the owner of the rental unit has a meritorious cause of action seeking reparation against any and all persons (lawful tenants or otherwise) responsible for any unwarranted damage to the property (e. g., walls and carpeting).
3. That no actions, legal processes, agreements, waivers, releases, etc., etc., pursued and/or brought about independently by the tenants in possession of the affected rental unit can defeat or in anyway diminished the owner's said cause of action.
The consequence being that if the OP were to sue the former occupant seeking reparations for the cost of repainting walls and replacing carpet as you propose, the latter would have an absolute defense based upon noncompliance with the standard rule, unless the property owner were to be joined as party claimant.
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A logic extension of your
postulation would enable one to whom you lent your automobile to sue the person that stole it because of the remote possibility that the borrower could be held liable to you because he left it running and unattended in front of the liquor store.