Will the next Congress (2021) be sworn in on a Sunday?
<p>The 20th Amendment of the U.S. Constitution states</p>
<blockquote>
<p>Section 1. The terms of the President and Vice President shall end at noon on the 20th day of January, and the terms of Senators and Representatives at noon on the 3d day of January, of the years in which such terms would have ended if this article had not been ratified; and the terms of their successors shall then begin.</p>
<p>Section 2. The Congress shall assemble at least once in every year, and such meeting shall begin at noon on the 3d day of January, <strong>unless they shall by law appoint a different day</strong>.</p>
</blockquote>
<p>Section 1 says that the <em>term</em> of the new Congress begins on January 3rd, but that is not the same thing as actually meeting and being sworn in.  Section 2 makes January 3rd the default date for that to happen, but also allows that date to be changed by law.</p>
<p><strong>January 3, 2021 is a Sunday.  Will the new Congress be sworn in on that day, or have they already designated a different day to be sworn in?</strong></p>

<p><strong>Final Result:</strong>  The 117th Congress did actually meet and swear in on a <em>Sunday</em>, January 3, 2021.  Per the other answer by @NateEldredge, this was the first Sunday swearing in for at least several decades.</p>
<hr />
<p><strong>December Update:</strong>  There still does not appear to be a bill to change the date of convening the 117th Congress.  However, an <a href="https://www.congress.gov/congressional-record/2020/12/20/senate-section/article/s7855-4" rel="noreferrer">entry in the Congressional Record for December 20, 2020</a> states this:</p>
<blockquote>
<p>Mr. GRASSLEY. Mr. President, today is Sunday, and I want to remember
what Senator Byrd said on a lot of Sundays when the Senate was in
session. He didn't say this because he didn't want to work on Sunday,
but he wanted everybody to remember the significance of Sunday for some
people, particularly Christians. He always said: ``Remember the Sabbath
and keep it holy.''</p>
<p>Now, I want to refer to another particular Sunday. <strong>Never in the
Senate's history has the Senate convened Congress -- meaning a new
Congress -- on a Sunday.</strong> The Constitution mandates that Congress convene
at noon on January 3, unless the preceding Congress, by law, designates
a different day.</p>
<p>Of course, January 3 has fallen on a Sunday over the last 238 years,
and <strong>each time, by unanimous consent, the Congress set a new convening
day other than that Sunday.</strong>  So now it appears, for the first time in
history, that Senate Democrats don't want to agree to such unanimous
consent and instead are insisting that the Senate start the 117th
Congress on Sunday.</p>
<p>I am not looking to get out of work. I have proven that I have
respect for attendance in the Senate. But out of respect, the Senate
usually does not have business on religious holidays observed by
members of various faiths.</p>
<p>So just like Senator Byrd, I also think the Lord's Day, particularly
when it is paired with the weight of starting a new Congress, deserves
reverence.</p>
<p>I yield.</p>
</blockquote>
<p>If Senator Grassley is correct, then all previous Congresses never allowed the convening date to fall on a Sunday.  Although there do not appear to be any bills formally introduced yet for the convening of the 117th Congress, his remarks above suggest that there has at least been discussion of the issue, and he accuses Senate Democrats of preventing the change of date.</p>

<h1>They will probably not be sworn in on a Sunday</h1>
<p>As far as I can tell, they have so far not passed a law to change the date.  However, you can see <a href="https://www.senate.gov/legislative/DatesofSessionsofCongress.htm" rel="nofollow noreferrer">here</a> a list of past dates of convening; they very frequently appoint a day different from January 3.  Checking the past dozen or so, they have never convened on a weekend, and they seem to avoid Mondays and Fridays as well.</p>
<p><a href="https://www.congress.gov/search?q=%7B%22source%22:%22legislation%22,%22search%22:%22%22day%20for%20the%20convening%22%22%7D&amp;searchResultViewType=expanded" rel="nofollow noreferrer">Here</a> you can see several recent instances of the legislation setting a different day for convening.  It seems like such bills have mostly been introduced in mid-November to early December.</p>
<p>So given the history, it seems likely that Congress will pass a law designating a different day, but hasn't yet gotten around to doing so.  My guess is that it will be Tuesday, January 5, 2021.</p>

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