S1983 plaintiff has to carry the burden on all disputed questions, including exigent circumstances.
Probable cause for custodial detention in own home after police entry, given proximity to scene of crime.
http://media.ca7.uscourts.gov/cgi-bin/rssExec.pl?Submit=Display&Path=Y2018/D08-17/C:17-1888:J:Ripple:aut:T:fnOp:N:2203888:S:0
Since 2011. An occasional commonplacing of the U.S. Circuit Courts of Appeal.
Neither an authoritative statement of the law nor legal advice. Quick work.