Error on prod server

[cafuego]

time="2015-11-05T11:30:04+11:00" level=info msg="Closed: https://github.com/previousnext/agov-answers/pull/35"
panic: runtime error: index out of range

goroutine 1 [running]:
main.sliceUrl(0xc20821d840, 0x4, 0x0, 0x0, 0x0, 0x0, 0xc208261700)
/opt/golang/src/github.com/nickschuch/close/main.go:90 +0x1c2
main.checkIssue(0xc20821d840, 0x4, 0x2)
/opt/golang/src/github.com/nickschuch/close/main.go:73 +0x15b
main.main()
/opt/golang/src/github.com/nickschuch/close/main.go:52 +0x352

goroutine 16 [select]:
net/http.(_persistConn).writeLoop(0xc208078370)
/usr/local/go/src/net/http/transport.go:945 +0x41d
created by net/http.(_Transport).dialConn
/usr/local/go/src/net/http/transport.go:661 +0xcbc

goroutine 15 [runnable]:
net/http.(_persistConn).readLoop(0xc208078370)
/usr/local/go/src/net/http/transport.go:928 +0x9ce
created by net/http.(_Transport).dialConn
/usr/local/go/src/net/http/transport.go:660 +0xc9f

goroutine 17 [syscall, locked to thread]:
runtime.goexit()
/usr/local/go/src/runtime/asm_amd64.s:2232 +0x1