Various experts have described the Pennsylvania congressional map drawn in 2011 as a partisan gerrymander drawn to benefit Republicans. Test after test found that the map was an extreme outlier, and in all three elections held under the map, in 2012, 2014, and 2016, Republicans won the same 13 out of 18 U.S. House seats.
The same 13 out of 18 seats, even as statewide votes split equally between Democrats and Republicans, even as Pennsylvania went for former President Barack Obama and then President Trump, former Gov. Tom Corbett and then Gov. Wolf, voted for U.S. Sens. Bob Casey and also Pat Toomey.
A group of Democratic voters, led by the League of Women Voters of Pennsylvania, sued over the map last year, saying it violated the state constitution by discriminating against Democrats. In January, the Pennsylvania Supreme Court agreed, overturning the map and ultimately imposing its own.
That decision set off a nasty political and legal fight and has upended politics across the state, drawing attention from across the country. Here's a full collection of our coverage of the case. We'll update it as new stories are published.
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June 15, 2017 — The League of Women Voters of Pennsylvania files a state lawsuit over the map, calling gerrymandering "one of the greatest threats to American democracy."
October 2017 — Commonwealth Court Judge Dan Pelligrini says in a hearing that the case would not be decided before the 2018 elections if it goes through the normal process: "I can tell you it isn't going to happen." On Oct. 16, he orders a stay in the suit. Lawyers for the plaintiffs ask the Pennsylvania Supreme Court to exercise a rarely used power to step in and fast-track the case.
Nov. 9, 2017 — The Pennsylvania Supreme Court agrees to take over and expedite the case, saying it "involves issues of immediate public importance." The court ordered the Commonwealth Court to hear a trial in the case, then submit findings of fact and conclusions of law to the high court by the end of the year. A one-week trial is scheduled to begin Dec. 11 before Judge P. Kevin Brobson in Harrisburg.
Nov. 16, 2017 — Senate President Pro Tempore Joe Scarnati (R., Jefferson) tries to move to lawsuit to federal court, but his House counterpart, House Speaker Mike Turzai (R., Allegheny) apparently disagrees. After a flurry of activity that day, the suit is returned to state court.
Dec. 11, 2017 — On the first day of trial in Harrisburg, University of Michigan political science professor Jowei Chen testifies for the plaintiffs that the 2011 map was more skewed toward Republicans than hundreds of maps that his computer software drew using politically neutral redistricting criteria. By comparing the actual map to the computer-drawn ones, Chen says, he determined that the partisan skew of the 2011 map was an "extreme statistical outlier."
Dec. 12, 2017 — West Chester University political science professor John J. Kennedy takes a different approach, testifying as an expert witness for the plaintiffs that the 2011 map also divides "communities of interest" that could and should have been kept together. Rather than using a quantitative approach to measuring the map, Kennedy walks through multiple districts' boundaries to show how the map combined some unrelated communities while splitting other groups.
Dec. 13-15 — The trial continues.
Dec. 29, 2017 — Commonwealth Court Judge P. Kevin Brobson recommends the state Supreme Court uphold the congressional map. In his recommended findings of fact and conclusions of law, he says the plaintiffs' experts were credible but the plaintiffs had not created a "judicially manageable standard" for the court to decide whether the map crossed the line. "Petitioners, however, have failed to meet their burden of proving that the 2011 Plan, as a piece of legislation, clearly, plainly, and palpably violates the Pennsylvania Constitution," he wrote. "For the judiciary, this should be the end of the inquiry."
Jan. 17, 2018 — The Pennsylvania Supreme Court hears oral argument in the case and appears open to the idea that the congressional map is illegally gerrymandered.
Jan. 22, 2018 — The Pennsylvania Supreme Court throws out the 2011 map, blocking its use in the 2018 midterm and general elections. The court gives the state legislature until Feb. 9 to submit a new map to Gov. Wolf, who has until Feb. 15 to approve it. If that does not happen, the court says, it will draw its own map by Feb. 19. While it says a full opinion will be released later, it tells the legislature that a new map should be composed of districts that are compact and contiguous, of equal population, and split as few counties and towns as possible. As the news ripples across the state and country, Republican lawmakers immediately vow to challenge the court.
Jan. 23, 2018 — Pennsylvania's top two Republican state lawmakers ask the Pennsylvania Supreme Court to stay its own order, a step they must take before going to the U.S. Supreme Court.
Jan. 25, 2018 — The lawmakers, Senate President Pro Tempore Joe Scarnati (R., Jefferson) and House Speaker Mike Turzai (R., Allegheny), ask the U.S. Supreme Court to step in and block the state Supreme Court order. In their request for a stay, the Republicans say the state court is taking power from the state legislature, overstepping its bounds under the U.S. Constitution.
Jan. 31, 2018 — As the political and legal fight grows increasingly nasty, Senate President Pro Tempore Joe Scarnati (R., Jefferson) tells the Pennsylvania Supreme Court that he will not hand over any data that would help the court draw its own lines. "In light of the unconstitutionality of the Court's Orders and the Court's plain intent to usurp the General Assembly's constitutionally delegated role of drafting Pennsylvania's congressional districting plan, Sen. Scarnati will not be turning over any data identified in the Court's Orders," his lawyers wrote.
Feb. 2, 2018 — Republican lawmakers open a new line of attack on the Pennsylvania Supreme Court, which they have already accused of partisanship. They accuse Justice David Wecht of bias based on comments he made on the campaign trail and also question whether Justice Christine Donohue was biased as well. Wecht should be disqualified from the case, they say.
Feb. 5, 2018 — U.S. Supreme Court Justice Samuel A. Alito Jr. rejects the Republican lawmakers' request for a stay without comment. He does not refer the issue to the whole court. The lawmakers say they will keep fighting, and a rank-and-file Republican lawmaker circulates a memo seeking cosponsors to join an attempt to impeach the Democratic justices of the Pennsylvania Supreme Court.
Feb. 7, 2018 — The Pennsylvania Supreme Court releases its opinion explaining its ruling. The 2011 map violated the state constitution's guarantee that "elections shall be free and equal," Justice Debra McCloskey Todd writes for the majority: "An election corrupted by extensive, sophisticated gerrymandering and partisan dilution of votes is not 'free and equal.'" Republican lawmakers criticize the opinion, do not rule out other legal attempts at fighting it, and say it is unlikely the legislature can draw and pass a new map before the Feb. 9 deadline in two days.
Feb. 8, 2018 — As it becomes clear that the state legislature will not draw and pass a new map in time for the court's Feb. 9 deadline, top Republican lawmakers say they are working on their own map that they will submit directly to Gov. Wolf.
Feb. 9, 2018 — Senate President Pro Tempore Joe Scarnati (R., Jefferson) and House Speaker Mike Turzai (R., Allegheny) submit a map directly to Gov. Wolf. Democratic lawmakers urge Wolf to reject the map, saying they were kept entirely out of the process. Democrats and experts begin analyzing the map and immediately criticize it as a partisan gerrymander, saying it looks cleaner than the previous map but remains unfairly skewed toward Republicans.
Feb. 13, 2018 — Wolf rejects the map, saying it remains a partisan gerrymander. He reached his conclusion in part based on an analysis done by Moon Duchin, a Tufts University math professor he hired. Wolf says he hopes the state legislature will submit a new map to him by Feb. 15, but participants in the case also begin preparing their own map proposals to submit directly to the court.
Feb. 15, 2018 — Participants in the case, including Wolf, House Democrats, and Senate Democrats, submit their proposals directly to the court. The court will now select a map or draw its own.
Feb. 19, 2018 — The Pennsylvania Supreme Court releases its map, drawn with the help of Stanford University law professor Nathaniel Persily. One thing is certain: Republican lawmakers are not going to stop fighting. The new map immediately upends politics in the state, including making Republican U.S. Rep. Ryan Costello's district more unfavorable for him.
As Scarnati and Turzai (R., Allegheny) prepare to ask the U.S. Supreme Court to intervene and block the map, the National Republican Congressional Committee says a group of national and state Republicans is preparing a second, separate federal challenge. (The NAACP and good-government group Common Cause also contemplate challenging the map, on civil rights grounds, but they ultimately decide not to.)
Feb. 20, 2018 — President Trump weighs in, saying he hopes Republicans fight the map "all the way to the Supreme Court, if necessary."
Feb. 21, 2018 — Top Republican state lawmakers file an emergency request with the U.S. Supreme Court, asking the nation's highest court to take up the case and block the new congressional map. They make essentially the same argument as before: The U.S. Constitution gives state legislatures the power to run elections, and the state court usurped that power by drawing its own map.
Feb. 22, 2018 — Making that same argument, a group of eight of the state's Republican congressmen and two state senate leaders file a federal lawsuit in Harrisburg, asking the court to block the map. (One incumbent Republican, U.S. Rep. Brian Fitzpatrick, does not join in the Republican challenges. "Gerrymandering attacks the bedrock right of every American to fair representation," he says.)
Meanwhile, as questions swirl about the possibility of trying to impeach state Supreme Court justices, experts said it would be difficult and should not be done.
Feb. 23, 2018 — The panel of federal judges assigned to the lawsuit filed by Republican congressmen and state senate leaders declines to immediately block the map but fast-tracks the schedule to hear the case.
Feb. 24, 2018 — President Trump weighs in again.
Feb. 28, 2018 — U.S. Supreme Court Justice Samuel A. Alito Jr. asks for responses to the Republican lawmakers' request for a stay, giving the participants in the case a chance to comment and allowing for "friend of the court" briefs from outside parties.
March 1, 2018 — In the lawsuit brought by Republican congressmen and state senators, the federal judges allow the voters in the initial case to step in to defend the map but do not allow the League of Women Voters of Pennsylvania or the National Democratic Redistricting Committee to intervene in the case. A hearing is scheduled for March 9.
March 2, 2018 — Gov. Wolf moves to dismiss the federal lawsuit that seeks to block the map, as does the group of Democratic voters who brought the original case. Wolf's legal team adds Neal Katyal, a former acting U.S. solicitor general who has argued multiple cases before the U.S. Supreme Court.
March 5, 2018 — Gov. Wolf, Democratic Lt. Gov. Mike Stack, and the Democratic voters who brought the original suit argue in court filings that the U.S. Supreme Court should not intervene to block the new congressional map. In one twist, former Pa. Gov. and U.S. Attorney General Dick Thornburgh files an amicus brief in support of Republicans' ask for a stay, putting him in opposition to his son David Thornburgh, the head of Philadelphia good-government group Committee of 70.
March 9, 2018 — At a hearing in the federal lawsuit that seeks to block the map, a panel of judges question lawyers on whether the court can and should intervene, what effects that could have, and whether to wait for the U.S. Supreme Court to take action first. The judges do not make any immediate decisions but say they will do so soon.
March 16, 2018 — With the deadline for filing to run just four days away, some congressional candidates hold out hope that a court will block the new congressional map, allowing them to revert to the old one. But with that deadline looming, they move forward with filing their papers to run in the newly drawn districts.
March 19, 2018 — The panel of federal judges rejects the Republican lawmakers' challenge to the congressional map, dismissing the lawsuit. The judges say the lawmakers do not have the proper standing. Within hours, the U.S. Supreme Court rejects top Republican lawmakers' request that the court steps in to block the map. With the two rejections, no challenges remain, clearing the way for the map to be used in the 2018 elections.
March 20, 2018 — One Republican state representative introduces resolutions to impeach four Pennsylvania Supreme Court justices for their rulings in the gerrymandering case. The measures, which have support from a small group of Republicans, receive a sharp rebuke from House Democrats.
Meanwhile, nearly 100 candidates file to run for congress by the 5 p.m. deadline, with 59 Democrats and 35 Republicans running for the 18 seats.
March 22, 2018 — Pennsylvania Supreme Court Chief Justice Thomas Saylor, who was elected as a Republican and dissented from the majority in the case, says he is "very concerned" about the effort to impeach his four colleagues. A key Republican, House Majority Leader Dave Reed, is resistant to the impeachment effort, saying he disagrees with the court's decision but "disagreement over the outcome of any particular case should not be grounds for impeachment."