Surprisingly, the rape need not be overly brutal. Lacerations and tearing frequently occur when a woman who is not sexually aroused has sex. That in itself is not evidence of a rape, since post-menopausal women who aren't on any kind of hormonal supplements may have such lacerations. They probably wouldn't have external bruising, however, if they had engaged in consensual sex. Similarly, a woman who has engaged in consensual "rough sex" may have external bruising but suffer no internal injuries whatsoever. (Without being too graphic, its all a matter of lubrication.) The degree of the internal damage, coupled with external bruising (especially in specific areas--inner thighs, upper arms) will indicate more accurately exactly what took place.
Tears, bruising, etc., will not be necessary for a successful prosecution for marital rape. All the woman has to do is say that a few months ago, her husband forced her to have sex against her will, and she just lay back and let him for, fear that he might get violent (despite having no history of same). The same is true with "date rape" cases and even allegations of sexual assault which are being brought forward 20 yrs after the supposed event.
The current view from the bench, engendered by radical feminism, is that women do not lie about such things. When it comes to a case of he said/she said, the male is most often convicted. Afterall, why would a tender, innocent, subjugated, paragon of virtue lie?