Thread by @mel_bough

NC Partisan gerrymandering day two thread -- we expect to hear from plaintiffs' experts today at 9 am. A few attorneys and a few audience members have already started trickling in the courtroom #ncga #ncpol

The attorneys in the room and a Campbell AV dude are currently trying to figure out where to place a giant TV for plaintiffs' presentation today #ncga #ncpol

It looks like the giant TV will be right in front of the @WRAL camera live streaming the trial... #ncga #ncpol

And we're back! Three-judge panel is in place, and it looks like @WRAL is managing with the giant TV. You can watch their live stream or stay tuned here for tweet updates! #ncga #ncpol

Jowei Chen is the first witness for the plaintiffs today -- he also testified in the federal partisan gerrymandering case in Greensboro (last year, I think) #ncga #ncpol

Chen is an associate professor of political science at the University of Michigan -- he is currently going over his background with Daniel Jacobson, attorney for the plaintiffs #ncga #ncpol

Chen's areas of expertise include geographic information systems, political geography, redistricting and legislative districts #ncga #ncpol

Chen studies computer simulated plans and he compares enacted redistricting plans to the simulated plans as baselines to look for things like partisan advantage and other forms of gerrymandering #ncga #ncpol

Chen has officially been approved to testify as an expert #ncga #ncpol

Chen was asked to evaluate 4 things: 1. whether partisan intent was dominant in 2017 redistricting plans -- He found that partisanship predominated at a statewide level as well as within county clusters #ncga #ncpol

The second thing Chen was asked to evaluate was the effect of the enacted plans on a number legislative races; he found the plans had the effect of producing fewer Dem districts than would have emerged if drawings would have followed traditional criteria #ncga #ncpol

Thomas Farr has objected to Chen's testimony about the third analysis, regarding #ncga adopted criteria. It was sustained #ncga #ncpol

Chen had said he found that Hofeller finished drafting much of 2017 maps well before adopted criteria in redistricting process. "Logically, Dr. Hofeller could not have been following the adopted criteria." #ncga #ncpol

Chen also said he found that Hofeller had been using racial data and not following the #ncga prohibition on using race data in the redistricting process #ncga #ncpol

The 4th, final issue Chen analyzed was how the 2017 plans affected individual House and Senate districts -- he found many plaintiffs were placed into partisan outlier districts when compared to computer simulated plans that followed the traditional adopted criteria #ncga #ncpol

We're getting into the weeds quick this morning -- Chen talking specific county groupings and county traversals and how he used them in his simulated plans #ncga #ncpol

Chen's first set of computer simulations only focuses on traditional redistricting criteria so he can create a baseline with which to analyze partisan intent #ncga #ncpol

His first set of data (simulated maps) -- which did not take incumbency protection or political data into consideration -- produced 1,000 maps #ncga #ncpol

Chen is talking about some of his findings and how he got to them. He's a very animated witness who is clearly excited about his work -- he's fun to watch #ncga #ncpol

Chen is going through parts of his expert report explaining how he reached the conclusion that the NC 2017 maps were extremely partisan gerrymandered #ncga #ncpol

Chen said he has been able to conclude with over 99% statistical certainty that the 2017 House plan is an extreme outlier #ncga #ncpol

Jowei Chen, an expert witness for the plaintiffs, is discussing something called a uniform swing and is about to get into describing a very complicated chart he created #ncga #ncpol

These are the charts that Chen is currently discussing #ncga #ncpol

Chen is now going to address his second set of simulated maps. In this set, he considered the traditional redistricting criteria but also set out to maximize incumbency protection #ncga #ncpol

Chen did this set because he wanted to see if incumbency protection could account for the extreme partisan outlier that the 2017 House plans were #ncga #ncpol

Chen says he was able to conclude from his second set of maps that incumbency protection cannot possibly explain or account for the extreme partisan bias in NC 2017 House map #ncga #ncpol

We're now on a 15-minute recess #ncga #ncpol

We are back from break, continuing with testimony from Jowei Chen, an expert witness for the plaintiffs in Common Cause v. Lewis #ncga #ncpol

Chen is now discussing the 2017 Senate plan and how it too is an extreme outlier #ncga #ncpol

There have been more documents filed today online in the NC partisan gerrymandering case, including expert reports and exhibits from trial bit.ly/2jVfOIB #ncga #ncpol

The documents filed also include transcripts from the trial yesterday -- that's the fastest I've seen from a court #ncga #ncpol

It appears that the Hofeller files, at least in part, are contained within this court document: bit.ly/2lhjHI7 #ncga #ncpol

At first glance, I don't have a clue as to what the Hofeller files mean. But I imagine redistricting experts would... #ncga #ncpol

The Hofeller files that are posted is just a lot of data, but also the formula the mapmaker used to create the maps #ncga #ncpol

We're still hearing from Jowei Chen, an expert witness for the plaintiffs. He's going over his report and computer map simulations in great detail #ncga #ncpol

Jowei Chen's expert report for the plaintiffs can be found in Exhibit 1 of this filing for anyone following along: bit.ly/2lkju6Z #ncga #ncpol

We're currently discussing page 79 of the report... #ncga #ncpol

We have just recessed for lunch. We'll be back at 2:30 with more testimony from Jowei Chen, an expert for the plaintiffs #ncga #ncpol

We are back from lunch and hearing now from Chen #ncga #ncpol

Chen is now talking about Hofeller's draft maps -- he compared them to the enacted maps from 2017 #ncga #ncpol

Chen said he wanted to assess the voracity of claims made by various experts that Dr. Hofeller was constrained by the adopted redistricting criteria or had been following the adopted criteria #ncga #ncpol

Jowei Chen's overlay analysis -- comparison of draft map to enacted map -- Hofeller assigned 97.6% of Census blocks containing 95.6% of the total NC population into draft Senate map before redistricting process #ncga #ncpol

In the draft House map, Chen said Hofeller assigned 99.9% (I think that's what he said) of Census blocks containing 88.2% of the total NC population before redistricting process #ncga #ncpol

Hofeller's draft plans were copied in June to become part of the enacted plan -- Chen discussed the computer history of the copies, which was displayed on a screen in the courtroom #ncga #ncpol

We're now looking at a draft copy of districts in Hoke and Cumberland and the enacted copy of the same districts -- they look near identical. These are from the Hofeller files #ncga #ncpol

So, 100% of the people in Senate district 21 of Hofeller's draft map were also assigned to the enacted map in the 2017 redistricting process #ncga #ncpol

And 99.42% of people in Senate district 19 were assigned to the same enacted district during the redistricting process #ncga #ncpol

Now we're going over the draft map and enacted map overlap in Senate districts 31 and 32 in Davie and Forsyth counties #ncga #ncpol

This is what we’re looking at — the percentage is the how many of the people in the draft districts were ultimately assigned to the enacted districts #ncga #ncpol

The draft plans for Durham, Granville and Person counties are completely identical to what lawmakers ultimately enacted, according to Chen #ncga #ncpol

The overlaps that Chen is talking about are important because the draft Hofeller maps were drawn in June 2017. The public redistricting process did not begin until July 26, 2017. The criteria for mapmaking was not adopted until Aug. 10, 2017. #ncga #ncpol

We're not to cross examination yet, but the legislative defendants have already argued in a prior hearing that this overlap analysis means nothing. It will be interesting to see how they show that #ncga #ncpol

Chen says he is able to conclude that Hofeller clearly could not have been following the publicly adopted redistricting criteria if he drew most of the maps 6 weeks prior #ncga #ncpol

Those were the Senate plans. Now Chen is going over his overlap analysis for the House plans #ncga #ncpol

Similarly to the Senate draft plans, the House originated from Hofeller's draft plan and his computer history *appears* to show the copying of one to another #ncga #ncpol

The first part of Chen's testimony about his House overlap analysis is about how the 12 Mecklenburg House districts are all at almost a 100% overlap with the final enacted plans #ncga #ncpol

Now we're going into Chen's finding that Hofeller used racial data in drafting the #ncga maps, despite specific adopted criteria that barred it #ncga #ncpol

#ncga leaders said in a public hearing that race was not part of Hofeller's database and that it couldn't even be viewed in his system #ncpol

#ncga made the same contention to a federal court during a racial gerrymandering case: "Data regarding the race of voters was not even loaded into the computer used by the map drawer to construct the districts" #ncpol

Plaintiffs are showing a screenshot of Hofeller's maptitude program -- Thomas Farr objected because the screenshot was not taken from Hofeller's computer. Objection overruled #ncga #ncpol

There was another objection over using analysis from @districks -- who was consulting for the plaintiffs. Judges overruled that objection too #ncga #ncpol

This is the screenshot we were looking at #ncga #ncpol

The screenshot shows the lineage of the enacted plans. It's the copy history, as I have very ineloquently been referring to -- Chen contends it shows Hofeller did not start from a "clean slate" as lawmakers previously said #ncga #ncpol

Jowei Chen, an expert for the plaintiffs in Common Cause v. Lewis, has been testifying about how Hofeller used race in maptitude, a mapmaking software #ncga #ncpol

We're taking a 15 min break before Chen delves more into what his takeaways were from the Hofeller files he analyzed, as well as the maptitude and Excel documents he reviewed #ncga #ncpol

Anddddd we're back with Chen! #ncga #ncpol

Chen says Hofeller made a note to himself about what safe Republican districts there were in draft plan #ncga #ncpol

Or rather, the note was about which districts were not safe for Republicans -- but either way, he said the note is remarkable because it shows partisan intent #ncga #ncpol

Chen says Hofeller checked pressure points for GOP incumbents, but not Democratic incumbents in the 2017 plans #ncga #ncpol

Chen is going over a file from Hofeller's documents that calculates the Republican vote shares from the @CommonCauseNC maps #ncga #ncpol

Chen says Hofeller was doing a partisan breakdown of the nonpartisan plan #ncga #ncpol

Jowei Chen is now offering rebuttal testimony to a legislative defendants' expert -- Farr objected and said their expert would not be testifying, but judges overruled for the time being (but can disregard testimony later if needed) #ncga #ncpol

The judges just called an end to the day -- we will resume with Jowei Chen, an expert for the plaintiffs, tomorrow at 9 a.m. #ncga #ncpol

We are also ending early tomorrow, at 3:30 p.m. due to a conflict one of the judges has, but counsel was told about it last week #ncga #ncpol