WCAG is supposed to give us a reasonably objective way of saying whether or not the sites we are building/auditing are "accessible" (to a particular baseline). However, they are only as useful as our understanding and interpretation of the actual guidelines' normative text. And of course they're not perfect - with some omissions, handwaving, and straight up loopholes. So where does this leave developers and auditors? In this talk, Patrick may not have all the answers, but he'll have a good rant around the subject anyway...

1. These aren't the SCs you're looking for...
(mis)adventures in WCAG 2.x interpretation and audits
Patrick H. Lauke / a11yTO / Toronto / 24 October 2019

2. about me...
▪ principal accessibility engineer at The Paciello Group
▪ occasional W3C AGWG member
▪ WCAG trash panda
▪ known for my rants, not my brevity...

3. what really grinds my gears...
▪ doing accessibility audits
▪ advising and reviewing the work of other engineers doing audits
▪ being active on accessibility mailing lists (WebAIM, W3C, ...)
...and far too often, the same question always bubbles up

4. “which success criterion can I
fail this under?”

6. ...it depends™

7. far too often, auditors clearly
dislike something, and look for
a justification to fail it ...

8. overstep the boundaries of
WCAG SCs
claim something has to be fixed/changed "to pass WCAG"
when it normatively doesn't

10. we are not lawyers (or judges)
but our audits and evaluations often have some legal dimension to them.
▪ evaluations should be as objective as possible
▪ evaluations should be consistent
...of course, this is easier said than done

11. WCAG is built on the idea that
success criteria can be
evaluated clearly, unambiguously
and consistently...
...but that's not always the case

12. only a few
cherry-picked examples ...
otherwise we'd be here a few more hours

13. WCAG success criteria are often
misunderstood and/or
misinterpreted
leads to wrong, or at least inconsistent, error reporting

15. 2.4.6 Headings and Labels (AA)
Headings and labels describe topic or purpose.
this doesn't mandate the use of headings and labels ... only that if a
page uses headings and labels, they must be descriptive.
it also doesn't mandate that headings and labels be correctly marked-up -
that's the job of 1.3.1 Info and Relationships and (where it affects
"accessible name" of controls) 4.1.2 Name, Role, Value ).
lastly, if labels aren't there, it's a 3.3.2 Labels or Instructions problem.
“

16. <input type="text">
passes 2.4.6 Headings and Labels
fails 3.3.2 Labels or Instructions
fails 4.1.2 Name, Role, Value

17. <p class="heading1">I'm a heading</p>
<p>First name</p>
<input type="text">
passes 2.4.6 Headings and Labels
fails 1.3.1 Info and Relationships
fails 4.1.2 Name, Role, Value

18. 3.3.2 Labels or Instructions (A)
Labels or instructions are provided when content requires user
input.
again, this doesn't mandate that labels be marked-up as <label> and
properly associated with form controls - that's covered by
1.3.1 Info and Relationships and (where it affects "accessible name" of
controls) 4.1.2 Name, Role, Value .
“

19. <p>First name</p>
<input type="text">
passes 3.3.2 Labels or Instructions
fails 4.1.2 Name, Role, Value
fails 1.3.1 Info and Relationships

20. 2.1.1 Keyboard (A)
All functionality of the content is operable through a keyboard
interface [...]
doesn't say anything about which keys are needed to operate
controls/functionality
“

21. <a href="#" onclick="..." role="button">fake button</a>
passes 2.1.1 Keyboard
even though it doesn't respond to SPACE like real button would

22. 3.2.3 Consistent Navigation (AA)
Navigational mechanisms that are repeated on multiple Web pages
within a set of Web pages occur in the same relative order each
time they are repeated, unless a change is initiated by the user.
this only normatively requires the relative order of navigation (in relation
to other page components) to be consistent - nothing more.
doesn't mandate that navigation should be same, work the same, etc
across pages
“

23. 1.3.3 Sensory Characteristics (A)
Instructions provided for understanding and operating content do
not rely solely on sensory characteristics of components such as
shape, color, size, visual location, orientation, or sound.
this only relates specifically to instructions ... and not whether or not
sensory characteristics are used - this is covered by other SCs, like
1.4.1 Use of Color or even 1.1.1 Non-Text Content .
“

24. WCAG success criteria and
cascades of fail ...

25. cascade of fail
<a href="..."> <img src="..."> </a>
fails multiple criteria ...need to consistently report these, but easy to
forget and tedious to do...

26. "speculative" cascade of fail
<div>Read more</div>
fails 2.1.1 Keyboard ... but also 4.1.2 Name, Role, Value
and if it acts as a link, also 2.4.4 Link Purpose (In Context) ?

27. auditor education / consistency
problems...
internal training and resources can help

28. more problematic are issues caused by
WCAG SCs that are vague ,
incomplete or otherwise
lacking

29. WCAG 2.x is not perfect
written by well-meaning, but fallible humans (after all)

30. WCAG success criteria can be
subjective ...

31. subjective interpretation?
▪ 1.1.1 All non-text content [...] has a text alternative that serves the
equivalent purpose - but what's the purpose?
▪ 1.3.1 Information, structure, and relationships conveyed through
presentation [...] - where do you draw the line?
▪ 2.4.6 Headings and labels describe topic or purpose - what's
"descriptive" exactly?

32. <div class="footer"> ... </div>
do you fail 1.3.1 Info and Relationships because they don't use
<footer> or role="contentinfo" ? is it not clear from context?
<a href="/">home</p>
<a href="...">products</a>
<a href="...">contact</a>
do you fail 1.3.1 Info and Relationships because they didn't wrap this in a
<ul> even when styled as an inline set of three links?

33. "I think what the
founding fathers of WCAG
meant to say..."

35. understanding documents and techniques try to clarify...
normative versus
non-normative

36. understanding / techniques can't
provide examples of
all possible scenarios

37. beyond the need for subjective interpretation
WCAG success criteria can have
odd loopholes ...

38. 2.4.7 Focus Visible (AA)
Any keyboard operable user interface has a mode of operation
where the keyboard focus indicator is visible.
but what does visible mean? it's not normatively defined...
“

39. a single extra pixel shown on focus is arguably visible

40. WCAG 2.1 decided not to modify
2.0 SCs, patched loopholes
with more SCs
but these new SCs also ended up having some loopholes

41. 1.4.11 Non-text Contrast (AA)
The visual presentation of the following have a contrast ratio of at
least 3:1 against adjacent color(s):
▪ User Interface Components: Visual information required to identify
user interface components and states [...]
▪ Graphical Objects: [...]
“

42. much better...that pixel has a 3:1 contrast ratio now

43. 1.4.11 Non-text Contrast (AA)
The visual presentation of the following have a contrast ratio of at
least 3:1 against adjacent color(s):
[...]
note that this only applies normatively to adjacent colors ... doesn't
apply to contrast between different colors used for states of the same
control
“

44. fails 1.4.11 Non-text Contrast

45. passes 1.4.11 Non-text Contrast

46. passes 1.4.11 Non-text Contrast.
but wait, does it fail 1.4.1 Use of Color ?

47. 1.4.1 Use of Color (A)
Color is not used as the only visual means of conveying
information, indicating an action, prompting a response, or
distinguishing a visual element.
but there's an escape clause in the non-normative F73 failure technique
that tries to redefine, by the backdoor, what "color" means...
“

48. F73: Failure of Success Criterion
1.4.1 due to creating links that are
not visually evident without color
vision
Note 1: Red and Pink are the same color (hue) but they have
different lightness (which is not color ). So red and pink would pass
the requirement for "not distinguished by color (hue) alone" since
they differ by lightness (which is not color) - as long as the
difference in lightness (contrast) is 3:1 or greater
WAT?
“

50. ...but we'll fix it in WCAG 2.2 (?)
2.4.11 Focus Visible Enhanced (Level AA)

51. SCs that are overly specific...
and then end up only applying to very specific cases

52. 1.4.10 Reflow (AA)
Content can be presented without loss of information or
functionality, and without requiring scrolling in two dimensions for:
▪ Vertical scrolling content at a width equivalent to 320 CSS pixels
▪ Horizontal scrolling content at a height equivalent to 256 CSS
pixels
[...]
meant to help low vision users that require up to 400% zoom, but ended up
too specific - only normatively applies at those exact values
“

53. @media ( width: 320px ) { ... }
codepen.io/patrickhlauke/pen/ZZqzaB

54. 1.4.12 Text Spacing (AA)
In content implemented using markup languages that support the
following text style properties, no loss of content or functionality
occurs by setting all of the following and by changing no other style
property:
▪ Line height (line spacing) to at least 1.5 times the font size
▪ Spacing following paragraphs to at least 2 times the font size
▪ Letter spacing (tracking) to at least 0.12 times the font size
▪ Word spacing to at least 0.16 times the font size
[...]
only those exact values and over - if content breaks/stops working at line
height of 1.4 instead of 1.5, not a failure...
“

55. use JavaScript to detect line height and fix only if 1.5 or higher
codepen.io/patrickhlauke/pen/jgVGOp

56. even after years of auditing,
I sometimes have weird
moments of realisation
seeing SCs, and what they say/apply to, in a new light

58. same discussions about
applicability and interpretation
even happen within the AGWG

59. WCAG success criteria need to
be testable ... but this doesn't
allow for nuance

60. WCAG SCs are binary
you either
pass or fail

61. sometimes the values/thresholds are just arbitrary lines in the sand ...

62. no weighting given to impact or
frequency of a particular fail,
or how bad a failure is off the
mark
sometime, you just want to say something's a minor or
soft fail , but distinction doesn't exist

63. fail a single SC and you can't
really claim to be conformant

64. loopholes , omissions and
subjective requirements can
and will be exploited
auditors aren't the only ones who try to find these gaps...

66. ...so what do we do about this?

68. join the debate/discussion (more open nowadays)
github.com/w3c/wcag/issues

69. more consistent Accessibility Compliance Testing (ACT)
w3.org/community/act-r

70. act-rules.github.io/rules

71. the next generation of accessibility guidelines...
w3.org/WAI/GL/task-forces/silver

72. moving away from binary pass/fail conformance (or trying)
www.w3.org/.../#Silver_Conformance

73. potentially complex scoring/rating system
more nuanced but too complex ?

74. ...in the meantime though...

75. don't creatively reinterpret
what an SC says
to fit your agenda
whether you're a developer or an auditor doing an evaluation

77. as auditor, you do your client a
disservice by not making clear
what is and isn't a
normative failure
...what happens when a clued-up client rightly challenges
your claim? all your other results lose credibility...

78. be conservative in your
pass / fail assessments
document your hesitation, clearly state when something's
"more of a suggestion" than a hard failure

79. further reading...

80. join my WCAG Trash Panda Webring :
▪ Fixes to WCAG 2.1 Understanding 2.4.6 and 3.3.2 #612
▪ Edits to 135 failure #890
▪ Proposal for color and contrast (1.3.1, 1.4.1, 1.4.3., 1.4.6, 1.4.11) #901
▪ Should role button and input button be a WCAG fail if cannot be activated
using space? #857
▪ Does SC 1.4.11 require comparing focused and non-focused states #541
▪ Ambiguity in understanding for 1.3.3 sensory characteristics #750
▪ Bad/incomplete example for Understanding 3.3.2 #755

81. ▪ "at least" should be "at most" in WCAG 2.1 SC 1.4.12 #635
▪ Expand 1.4.10 to apply 'down to' instead of 'at' #698
▪ 2.4.7 Focus Visible - what counts as "visible"? #302
▪ Must the tooltip of icons match the accessible name? (for "Label in Name",
SC 2.5.3) #891
▪ Keyboard operation with assistive technology: 2.1.1 or 4.1.2? #878
▪ Can title on links (e.g. linked icon) as sole source of accName ever pass
1.1.1? #867 (side discussion about high contrast mode and reponsibility of
user agents)
▪ Error of the User Agents part of WCAG or not #866

82. ▪ 1.4.5 / 1.4.9 Image of Text and <text> inside SVGs #773
▪ Revisiting imbalance between 1.2.4 Captions (Live) (AA) and 1.2.9 Audio-
only (Live) (AAA) #795
▪ ARIA in HTML conformance to conform WCAG ? #717
▪ Failure technique F94 (1.4.4 resize text): remove "1280 pixels wide" step in
test procedure #704
▪ Contrast Ratio Math and Related Visual Issues #695
▪ Include font weight for color contrast tests #665
▪ Accessible P Tag Usage (WebAim)

83. ▪ Must the tooltip of icons match the accessible name? (for "Label in Name",
SC 2.5.3) #891
▪ Are Reflow, Text Size and Orientation cumulative? #391
▪ What does "support the following text style properties" mean (1.4.12)?
#884
▪ Does using the placeholder with a value alone pass 3.3.2 Labels or
Instructions? #864
▪ Using color ALONE as focus indicator #757
▪ New SC for keyboard operation? #872

84. @patrick_h_lauke
github.com/patrickhlauke/
paciellogroup.com
splintered.co.uk