diff --git a/include/core/problem/problem.h b/include/core/problem/problem.h
index aae0dfb0cda3fc03d13b13b5f6c50cc460301a3c..a7432b15148d942630fa470ea79331d0ca074059 100644
--- a/include/core/problem/problem.h
+++ b/include/core/problem/problem.h
@@ -234,7 +234,7 @@ class Problem : public std::enable_shared_from_this<Problem>
          *   - This decision is made at problem level, not at processor configuration level.
          *   - Therefore, if you want to permanently configure a processor for not creating key frames, see Processor::voting_active_ and its accessors.
          */
-        bool permitKeyFrame(ProcessorBasePtr _processor_ptr);
+        bool permitKeyFrame(ProcessorBasePtr _processor_ptr) const;
 
         /** \brief New key frame callback
          *
@@ -250,7 +250,7 @@ class Problem : public std::enable_shared_from_this<Problem>
          *   - This decision is made at problem level, not at processor configuration level.
          *   - Therefore, if you want to permanently configure a processor for not creating estimated frames, see Processor::voting_active_ and its accessors.
          */
-        bool permitAuxFrame(ProcessorBasePtr _processor_ptr);
+        bool permitAuxFrame(ProcessorBasePtr _processor_ptr) const;
 
         /** \brief New auxiliary frame callback
          *
diff --git a/src/problem/problem.cpp b/src/problem/problem.cpp
index 37a841abeeaf8caf6daf56f12d3f00689bd3aa6d..0792acf906bd3f252370bdf7695bb36ed8170f0b 100644
--- a/src/problem/problem.cpp
+++ b/src/problem/problem.cpp
@@ -404,7 +404,7 @@ Eigen::VectorXs Problem::zeroState() const
     return state;
 }
 
-bool Problem::permitKeyFrame(ProcessorBasePtr _processor_ptr)
+bool Problem::permitKeyFrame(ProcessorBasePtr _processor_ptr) const
 {
     // This should implement a black list of processors that have forbidden keyframe creation
     // This decision is made at problem level, not at processor configuration level.
@@ -425,7 +425,7 @@ void Problem::keyFrameCallback(FrameBasePtr _keyframe_ptr, ProcessorBasePtr _pro
                 processor->keyFrameCallback(_keyframe_ptr, _time_tolerance);
 }
 
-bool Problem::permitAuxFrame(ProcessorBasePtr _processor_ptr)
+bool Problem::permitAuxFrame(ProcessorBasePtr _processor_ptr) const
 {
     // This should implement a black list of processors that have forbidden auxiliary frame creation
     // This decision is made at problem level, not at processor configuration level.