Does having sex with a mentally ill person voluntarily still commit rape in Vietnam?

Specifically, at the judgment 37/2019/HSST dated May 16, 2019 for rape of the People's Court of Chon Thanh district, Binh Phuoc province as follows:

Hoang Huynh D rents room number 05 at " Nhat Thi" inn (inn) in group 1, hamlet 8, commune M, district Ch owned by Vu Thi Nhat T to live alone and work as a worker in Minh Hung III Industrial Park. During the rental period, He knew that Quach Thi Hue Th (commonly known as Be), born on June 17, 2001 had a mental illness and could not communicate, speak loudly and clearly like a normal person, and was living with his father and mother in room number 01 inn.

At about 19 o'clock, D walked to Mr. Loi's grocery store to buy 01 bottle of mineral water and saw Ms. Th standing near room number 01. Then, D took the water bottle and turned to ask Ms. Th if she had a drink, Ms.Th shake her head (meaning not drinking), D continued: "Do you have a lover?", Ms. Th continued to shake her head, D said: "I love you", Ms. Th nodded (meaning agreeing to love D). Using her mobile phone to light the way ahead, Ms. Th followed him to an open field with lots of bushes and trees next to Mr. Loi's boarding house to have sex with Ms. Th..."

The court declared defendant Hoang Huynh D guilty of "rape", and sentenced him to two (02) years in prison.

Acts constituting a crime, the level of punishment, and the penalty frame for the crime of rape are specified in Article 141 of the 2015 Criminal Code of Vietnam as follows:

Article 141. Rape

Any person who uses violence or threatens to use violence or takes advantage of the victim's defenselessness or otherwise engages in non-consensual sexual intercourse or other sexual activities shall face a penalty of 02 - 07 years' imprisonment.

2. This offence committed in any of the following circumstances carries a penalty of 07 - 15 years' imprisonment:

a) The offence is committed by an organized group;

b) The offence is committed against a person for whom the offender is responsible for providing care, education or medical treatment;

c) The offence is committed by more than one person against one person;

d) The offence has been committed more than once;

dd) The offence is committed against 02 or more people;

e) The offence is of an incestuous nature;

g) The offence results in the victim's pregnancy;

h) The offence causes 31% - 60% WPI for the victim;

i) The victim suffers from 11% - 45% mental and behavioral disability because of the offence;

In the above case, Hoang Huynh D took advantage of the victim's defenseless state to intentionally have sex, which means there were signs of rape. In some cases, mental victims may still be able to perceive the behavior of others, but due to their limited cognitive ability, they have not fully appreciated the dangerous nature and consequences of their behaviour, so having intercourse with a psychopath - even if the victim volunteered - is still prosecuted for criminal responsibility.

However, when a person has sex with a mentally ill person, two cases must be distinguished.

- If that person knows that the victim is mentally ill but still intentionally has sex for satisfaction, he still commits rape.

- In case, the subject performs the act without knowing the victim is mentally ill (between two people who do not know each other before and the victim does not have any abnormal signs to force others to know that they are mentally ill) and both parties voluntarily have sex (the victim is 18 years or older), this act may not constitute rape.

Many people compare it to the law and think that to constitute rape, there must be an act of "using force, threatening to use force" or other tricks to have "unwilling intercourse" before being prosecuted for criminal responsibility. But, having sex between a man who is capable of criminal responsibility and a woman who has lost the ability to perceive and control behavior is rape, because the person who has lost the ability to perceive and control behavior is considered defenseless.