Legal Question in Family Law in New Mexico

Re: subject

I am not 100% certain regarding the issue of "illegal" but, I am fairly certain the answer is NO.

Now, that does not mean that the person aggrieved cannot sue both the married person and the unmarried person. I have read in recent years where the wife sued the husband's new girlfriend. The basis would be something like mental distress; and something like intentional distress or attempted destruction of the marital relationship. The wife could probably also sue the husband for breach of fiduciary duty to the marital relationship since the husband will have to begin to pay child support to the pregnant girlfriend. Essentially, part of that child support money is community money that should be made available to wife - and, now it is not available because of his actions.

Good luck.