That any person who shall, without the permission of the owner and without having any color of title thereto, enter upon the lands of another, and shall refuse to remove therefrom after three days' notice, shall be deemed guilty of unlawful detainer and may be removed from such lands.

Unlawful detainer defined: RCW 59.12.030.

The complaint in all cases under the provisions of this chapter shall be upon oath, and there shall be embodied therein or amended thereto an abstract of the plaintiff's title, and the defendant shall, in his or her answer, state whether he or she makes any claim of title to the lands described in the complaint, and if he or she makes no claim to the legal title but does claim a right to the possession of such lands, he or she shall state upon what grounds he or she claims a right to such possession.

It shall not be necessary for the plaintiff, in proceedings under this chapter, to allege or prove that the said lands were, at any time, actually occupied prior to the defendant's entry thereupon, but it shall be sufficient to allege that he or she is the legal owner and entitled to the immediate possession thereof: PROVIDED, That if the defendant shall, by his or her answer, deny such ownership and shall state facts showing that he or she has a lawful claim to the possession thereof, the cause shall thereupon be entered for trial upon the docket of the court in all respects as if the action were brought under the provisions of *chapter XLVI of the code of eighteen hundred and eighty-one.

*Reviser's note: "chapter XLVI of the code of eighteen hundred and eighty-one" is codified as RCW 7.28.010, 7.28.110 through 7.28.150, and 7.28.190 through 7.28.270.

All persons in actual possession of any portion of the several subdivisions of any section of land, according to the government surveys thereof, may be made defendants in one action: PROVIDED, That they may, in their discretion, make separate answers to the complaint, and if separate issues are joined thereupon, the same shall nevertheless be tried as one action, but the verdict, if tried by jury, shall find separately upon the issues so joined, and judgment shall be rendered according thereto.