biblatex gives incorrect sequencing by using all given name initials

Question

I am using Ubuntu 20.04, with TeXLive2019, Biber 2.14 and BibLaTeX 3.1. In the pdf produced from the following MWE by running xelatex, the (single-author) Jaffe2014 citation is listed after the (multi-author) Jaffe2003 citation. My understanding, on the contrary, is that all single-author items should appear first, sorted in year order and then alphabetical order of title, followed by multi-author items, sorted in alphabetical order of author, then year order and then alphabetical order of title.

\documentclass[a4paper, 12pt, table]{report}

\begin{filecontents}{testseq.bib}
@Misc
{
    Jaffe2003c,
    author = "Jaffe, P and Lemon, N and Poisson, S",
    publisher = "Centre for Children and Families in the Justice System",
    title = "{Child custody and domestic violence: A call for accountability}",
    year = "2003",
}

@Article
{
    Jaffe2014a,
    author = "Jaffe, Peter G",
    journal = "{Family Court Review}",
    number = "2",
    pages = "187--192",
    title = "{A presumption against shared parenting for family court litigants}",
    volume = "52",
    year = "2014",
}
\end{filecontents}

\usepackage[style=apa, sortcites=true, backend=biber, uniquename=false]{biblatex}
\DeclareLanguageMapping{english}{english-apa}
\addbibresource{testseq.bib}

\begin{document}

\chapter{Some text}

\textcite{Jaffe2014a} talks about this, and this is where we quote him again \parencite{Jaffe2003c}. 

\printbibliography

\end{document}  

The reason appears to be that Jaffe2003 has the author listed as "Jaffe, Peter G", while Jaffe2014 has him listed as "Jaffe, P". When these are reduced to initials and sorted, "Jaffe, P" will come before "Jaffe, PG". (Incidentally, unless I use "uniquename=false", I get the same disambiguation in the text itself -- "P.G. Jaffe (2014)" and "(P. Jaffe et al., 2003)" -- even though the manual (p67) says that the default here is "false", which should mean that this argument is not needed -- though perhaps I am missing something here.)

While I could go through the bibfile and edit all the entries to show only first names or initials, I'm assuming that there must be an incantation somewhere in Biber/BibLaTeX that restricts its sorting to given name initials only, and only uses additional given names or initials as a subsort criterion. Sadly, having perused the 338 pages of the manual, I can't find anything that bears on this.

Can anyone help me get the citations to sequence correctly?

Answer 1

BibTeX and biblatex do not differentiate between first name and middle names. The given name encompasses both first name and middle names. So you can not easily tell biblatex to ignore middle names for sorting purposes.

If you want to force a certain sorting, I suggest you use the sortname field.

\documentclass[a4paper, 12pt]{article}

\begin{filecontents}{\jobname.bib}
@misc{Jaffe2003c,
  author    = {Jaffe, P. and Lemon, N. and Poisson, S.},
  publisher = {Centre for Children and Families in the Justice System},
  title     = {Child Custody and Domestic Violence: A Call for Accountability},
  year      = {2003},
}
@article{Jaffe2014a,
  author   = {Jaffe, Peter G.},
  sortname = {Jaffe, P.},
  journal  = {Family Court Review},
  number   = {2},
  pages    = {187--192},
  title    = {A Presumption Against Shared Parenting for Family Court Litigants},
  volume   = {52},
  year     = {2014},
}
\end{filecontents}

\usepackage[style=apa, backend=biber, uniquename=false]{biblatex}
\addbibresource{\jobname.bib}

\begin{document}
\textcite{Jaffe2014a} talks about this,
and this is where we quote him again \parencite{Jaffe2003c}. 

\printbibliography
\end{document}