diff --git a/code/IO.f90 b/code/IO.f90
index 72f0e0258..da523ca6c 100644
--- a/code/IO.f90
+++ b/code/IO.f90
@@ -1229,21 +1229,29 @@ endfunction
  case (205_pInt)
    msg = 'unknown lattice structure encountered'
 
+ case (210_pInt)
+   msg = 'unknown material parameter for j2 constitutive phase:'
  case (211_pInt)
    msg = 'material parameter for j2 constitutive phase out of bounds:'
  case (212_pInt)
    msg = 'unknown constitutive output for j2 constitution:'
 
+ case (220_pInt)
+   msg = 'unknown material parameter for phenopowerlaw constitutive phase:'
  case (221_pInt)
    msg = 'material parameter for phenopowerlaw constitutive phase out of bounds:'
  case (222_pInt)
    msg = 'unknown constitutive output for phenopowerlaw constitution:'
 
+ case (230_pInt)
+   msg = 'unknown material parameter for titanmod constitutive phase:'
  case (231_pInt)
    msg = 'material parameter for titanmod constitutive phase out of bounds:'
  case (232_pInt)
    msg = 'unknown constitutive output for titanmod constitution:'
 
+ case (240_pInt)
+   msg = 'unknown material parameter for dislotwin constitutive phase:'
  case (241_pInt)
    msg = 'material parameter for dislotwin constitutive phase out of bounds:'
  case (242_pInt)
@@ -1251,6 +1259,8 @@ endfunction
  case (243_pInt)
    msg = 'zero stacking fault energy'
 
+ case (250_pInt)
+   msg = 'unknown material parameter for nonlocal constitutive phase:'
  case (251_pInt)
    msg = 'material parameter for nonlocal constitutive phase out of bounds:'
  case (252_pInt)
diff --git a/code/constitutive_dislotwin.f90 b/code/constitutive_dislotwin.f90
index bf566aa56..d252991a3 100644
--- a/code/constitutive_dislotwin.f90
+++ b/code/constitutive_dislotwin.f90
@@ -296,6 +296,8 @@ do                                                       ! read thru sections of
      positions = IO_stringPos(line,maxNchunks)
      tag = IO_lc(IO_stringValue(line,positions,1))        ! extract key
      select case(tag)
+       case ('constitution')
+         cycle
        case ('(output)')
          output = output + 1_pInt
          constitutive_dislotwin_output(output,i) = IO_lc(IO_stringValue(line,positions,2_pInt))
@@ -394,6 +396,8 @@ do                                                       ! read thru sections of
               constitutive_dislotwin_sbResistance(i) = IO_floatValue(line,positions,2_pInt)
        case ('shearbandvelocity')
               constitutive_dislotwin_sbVelocity(i) = IO_floatValue(line,positions,2_pInt)
+       case default
+              call IO_error(240_pInt,ext_msg=tag)
      end select
    endif
 enddo
diff --git a/code/constitutive_j2.f90 b/code/constitutive_j2.f90
index ebce4b2a8..bff742166 100644
--- a/code/constitutive_j2.f90
+++ b/code/constitutive_j2.f90
@@ -151,6 +151,8 @@ subroutine constitutive_j2_init(file)
      positions = IO_stringPos(line,maxNchunks)
      tag = IO_lc(IO_stringValue(line,positions,1_pInt))                                                                            ! extract key
      select case(tag)
+       case ('constitution')
+         cycle
        case ('(output)')
          output = output + 1
          constitutive_j2_output(output,i) = IO_lc(IO_stringValue(line,positions,2))
diff --git a/code/constitutive_nonlocal.f90 b/code/constitutive_nonlocal.f90
index 3686412ca..d5b55388f 100644
--- a/code/constitutive_nonlocal.f90
+++ b/code/constitutive_nonlocal.f90
@@ -440,6 +440,8 @@ do
         constitutive_nonlocal_rhoSglScatter(i) = IO_floatValue(line,positions,2_pInt)
       case('surfacetransmissivity')
         constitutive_nonlocal_surfaceTransmissivity(i) = IO_floatValue(line,positions,2_pInt)
+      case default
+        call IO_error(250_pInt,ext_msg=tag)
     end select
   endif
 enddo
diff --git a/code/constitutive_phenopowerlaw.f90 b/code/constitutive_phenopowerlaw.f90
index e9c23124f..f6803f3a3 100644
--- a/code/constitutive_phenopowerlaw.f90
+++ b/code/constitutive_phenopowerlaw.f90
@@ -272,6 +272,8 @@ subroutine constitutive_phenopowerlaw_init(file)
      positions = IO_stringPos(line,maxNchunks)
      tag = IO_lc(IO_stringValue(line,positions,1_pInt))   ! extract key
      select case(tag)
+       case ('constitution')
+         cycle
        case ('(output)')
          output = output + 1_pInt
          constitutive_phenopowerlaw_output(output,i) = IO_lc(IO_stringValue(line,positions,2_pInt))
@@ -346,6 +348,8 @@ subroutine constitutive_phenopowerlaw_init(file)
        case ('interaction_twintwin')
               forall (j = 1_pInt:lattice_maxNinteraction) &
                 constitutive_phenopowerlaw_interaction_twintwin(j,i) = IO_floatValue(line,positions,1_pInt+j)
+       case default
+              call IO_error(220_pInt,ext_msg=tag)
      end select
    endif
  enddo
diff --git a/code/constitutive_titanmod.f90 b/code/constitutive_titanmod.f90
index bb99f5f5e..383796f22 100644
--- a/code/constitutive_titanmod.f90
+++ b/code/constitutive_titanmod.f90
@@ -398,6 +398,8 @@ enddo
      positions = IO_stringPos(line,maxNchunks)
      tag = IO_lc(IO_stringValue(line,positions,1_pInt))   ! extract key
      select case(tag)
+       case ('constitution')
+         cycle
        case ('(output)')
          output = output + 1_pInt
          constitutive_titanmod_output(output,i) = IO_lc(IO_stringValue(line,positions,2_pInt))
@@ -584,6 +586,8 @@ enddo
               forall (j = 1_pInt:lattice_maxNinteraction) &
                 constitutive_titanmod_interactionTwinTwin(j,i) = IO_floatValue(line,positions,1_pInt+j)
                 write(6,*) tag
+       case default
+              call IO_error(230_pInt,ext_msg=tag)
      end select
    endif
 enddo