From one of the most important English-language sources for the content of Islamic law: Reliance of the Traveller: A Classic Manual of Islamic Sacred Law:
It is certified by Al-Azhar University as a translation that "corresponds to the Arabic original and conforms to the practice and faith of the orthodox Sunni Community...":
Here is the certification in Arabic:
Note that this Sharia manual also garners respect in the USA. Dr. Alan Godlas, Associate Professor of Religion at the University of Georgia, calls it a "carefully translated manual of the proper practice of Islam (shari'a) according to the Shafi'i madh'hab. It has been an essential book in the library of any serious English speaking Muslim or scholar of Islam since its publication in 1991."
In Book O, titled "Justice," in section 1, "Who is Subject to Retaliation for Injurious Crimes," section o1.1 reads, "Retaliation is obligatory ... against anyone who kills a human being purely intentionally and without right...":
However, o1.2 clarifies (above) that "The following are not subject to retaliation" and then lists — after the lovely, egalitarian "Muslim for killing a non-Muslim" and "Jewish or Christian subject ... for killing an apostate" — "(4) a father or mother (or their fathers or mothers) for killing their offspring, or offspring's offspring":
A manual of Islamic law certified as a reliable guide to Sunni orthodoxy by Al-Azhar University, the most respected authority in Sunni Islam, says that "retaliation is obligatory
against anyone who kills a human being purely intentionally and without right." However, "not subject to retaliation" is "a father or mother (or their fathers or mothers) for killing their offspring, or offspring's offspring." ('Umdat al-Salik o1.1-2). In other words, someone who kills his child incurs no legal penalty under Islamic law.
Syria in 2009 scrapped a law limiting the length of sentences for honor killings, but "the new law says a man can still benefit from extenuating circumstances in crimes of passion or honour 'provided he serves a prison term of no less than two years in the case of killing.'" And in 2003 the Jordanian Parliament voted down on Islamic grounds a provision designed to stiffen penalties for honor killings. Al-Jazeera reported that "Islamists and conservatives said the laws violated religious traditions and would destroy families and values."
Muslim countires living under the sharia have more lenient sentences for honor murder.